Page 1 of 1

C19 Stretch and re-build - Launched!!

Posted: Mon Nov 27, 2017 12:22 pm
by TomTom
I am moving my C19 issues over here - and keeping my fingers crossed at this stage that it may become a "re-build" ...

I have managed to cut out the center console, the front locker and the motor well bulkhead, remove the floor and dig out all the foam and chase tubes.

She is one sorry looking mess at the moment.

I am waiting for a multi tool I have ordered (never knew about them till the other day) and am hoping I will be able to cut out the stringers and frames neatly - and possibly all in one - so that if they are sound, they can go right back in once I have redone the keel, chines and fabric.

They have come away from the hull on the Port side, but it seems most of the resin cured on the starboard side.

Once I have all frames and stringers out, I am hoping we can grind off that gooey mess and start again.

The hull is on its trailer and has been braced all round.

I am hoping most of the issues where resin not curing and not water ingress.

The plywood still seems sound from visually inspecting, but I am waiting for the moisture meter I ordered before I can really say anymore.

Here are some pics...

Image
Image
Image

Re: C19 - Major Structural Issues - Progress

Posted: Mon Nov 27, 2017 1:02 pm
by glossieblack
TomTom wrote: Mon Nov 27, 2017 12:22 pm I am moving my C19 issues over here - and keeping my fingers crossed at this stage that it may become a "re-build" ...
We'll all be keeping our fingers crossed. Well done on keeping your cool and finding a feasible way through.

Re: C19 - Major Structural Issues - Progress

Posted: Mon Nov 27, 2017 2:09 pm
by Fuzz
It would be wonderful if you are able to fix the issues and save the boat. You did such a nice job building it that it would be a crying shame if you have to scrape it.
As for cutting the stringers loose with the multi-tool it can be done. That is what I used on the boat I am rebuilding now. I only had to cut 18 inches or so out on four stringers. The multi-tool did a great job but it is not very fast and you have a lot of running feet to cut out. The blades are spendy and you will need to carbide tipped ones for this task. I know some narrow minded folks here :lol: do not care for multi-tools but mine has been a huge help at times. Depending on how fast it goes and your cost of blades you might find it more cost and time effective to just sacrifice the stringers. Only time will tell but best of luck either way you go.

Re: C19 - Major Structural Issues - Progress

Posted: Mon Nov 27, 2017 2:37 pm
by cape man
You are a strong and brave man!

Re: C19 - Major Structural Issues - Progress

Posted: Tue Nov 28, 2017 8:55 am
by pee wee
I don't know if you coated the ply with resin before you laid the glass down, or if you allowed the resin to soak through the glass to the plywood on the inside of the hull, but wouldn't the resin have coated and somewhat waterproofed the ply even if it never set up? Maybe raw resin or hardener mixes with water eventually, but maybe not . .

I'm an optimist, and I hope you can get that boat back on the water! Good thing you noticed a problem when you did, wouldn't do to have things go south out on the water.

Re: C19 - Major Structural Issues - Progress

Posted: Tue Nov 28, 2017 9:16 am
by justin_dwyer
Good luck TomTom, I feel you man!
I love your boat to, so hope you get her back out there.
Justin

Re: C19 - Major Structural Issues - Progress

Posted: Tue Nov 28, 2017 10:14 am
by tcason
I am shedding a tear looking at that............

Good luck!!

Re: C19 - Major Structural Issues - Progress

Posted: Tue Nov 28, 2017 3:46 pm
by peter-curacao
Ahh men that sucks, hope you got her up and running again fast

Re: C19 - Major Structural Issues - Progress

Posted: Tue Nov 28, 2017 4:38 pm
by jacquesmm
cape man wrote: Mon Nov 27, 2017 2:37 pm You are a strong and brave man!
I agree with that.

Re: C19 - Major Structural Issues - Progress

Posted: Tue Nov 28, 2017 6:47 pm
by Eric1
Good for you! Sorry you have to go through this but you are doing the rework the right way. :)

Re: C19 - Major Structural Issues - Progress

Posted: Wed Nov 29, 2017 2:35 pm
by fallguy1000
Making the right moves TT. The multitool needs to have carbide blades and you might go through a few so buy at least a 3 pack when you order or you'll be waiting.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Nov 29, 2017 2:38 pm
by fallguy1000
So, a question. Does the laminate leave the plywood further up into the hull? i.e. Did you tap test the areas above the sole? They would be suspect to a degree.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Nov 29, 2017 3:55 pm
by TomTom
I am not sure I fully understand about the laminate leaving the plywood above the hull?

Towards the bow, in the locker (on the left of the picture), the biaxial fabric has delaminated from the plywood (due I believe) to epoxy not curing.

Remember that as the boat narrows towards the bow, the same 50 inch wide fabric that is laid along (or just over) the keel, reaches higher and higher up the sides (and I don't think that I trimmed it) - so it is all part of the same "batch' of resin that didn't cure properly.

The Starboard side is much more firm. Even getting the stringers off is proving pretty tough on that side.

Either way, multimeter arrives tomorrow!

Just wondering what best to calibrate it against?

Re: C19 - Major Structural Issues - Progress

Posted: Wed Nov 29, 2017 3:59 pm
by TomTom
I think elsewhere above the sole if the resin had issues, the paint would have bubbled like it did in the locker - those bubbles were there not long after I launched her - and I put it down to bad surface prep pre painting - and ignored them (as they were out of sight)!

I suspect my stringers may have been floating on an uncured layer of epoxy for quite a while now; and probably the bouncy foam, a sturdy floor, good design etc. was enough that it never became apparent earlier.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Nov 29, 2017 7:47 pm
by fallguy1000
You mean moisture meter. I'd calibrate it against something in your house unless you have windows open all the time. Set the thing for a wood that is close as needed and test wood in your home. Take a number of samples and record them. Then take some samples of exterior wood that can't get rained on, like plywood soffits, for example. Get an idea for inside ambient MC and outside ambient MC and decide the averages. Your boat ideally dries to inside ambient MC before glassing and cannot exceed outside ambient MC or is considered wet by my standards.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Nov 29, 2017 7:53 pm
by fallguy1000
Ambient inside MC here in Minnesota is about 6-8%. Outside ambient varies seasonally down to 12%, up to say 15%, depends on the season. That should help you a bit. If your boat is over 15% on an accurate wood setting; it is pretty surely wet.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Nov 29, 2017 8:19 pm
by fallguy1000
So, let's use my numbers. Say 7% inside ambient and 13.5% outside ambient. If your boat, when meter is set right reads 17%, then it is technically wet. Wet on the bottom, I'd scrap the boat. I doubt it will be that, but let's say you read 12 on the bottom and 15 on the top; you will know you are too wet to glass it back up on top, but will be okay with the bottom.

All examples.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Nov 29, 2017 10:34 pm
by TomTom
Am I missing a key point - why do you think it will be wetter up top?

Do you mean above the sole/floor?

On the hull sides?

Re: C19 - Major Structural Issues - Progress

Posted: Wed Nov 29, 2017 11:04 pm
by fallguy1000
I expect the boat to be wetter on the topside of the hull bottom in the areas where you had ingress. I'm pretty sure you'll be fine. In fact, those wetter areas will be a good gauge of bad for you. If you gauge the bottom of the hull where you used the other epoxy; you should get an idea of the boat's static state. If it is wetter on the bottom of the boat than say a fencepost in your yard; you are in trouble. If it is wetter in the bilge, say, than the fencepost in the yard; you can dry that out.

Write everything down and record things in a notebook. Make sure you have good batteries in the unit, mine f's up before the battery indicator says its bad batteries. The boat should be about as dry as indoor lumber, or at least close before you glass it back up. (my computer went to sleep before I finished the original post).

Re: C19 - Major Structural Issues - Progress

Posted: Wed Nov 29, 2017 11:16 pm
by TomW1
TomTom don't worry about things until you get your probe and can test your wood. Then you want it to test at 10-12 percent or lower. If you have gotten all the gunk out and are drying the boat you should be ok.

Good luck guy. Your build was an inspiration for a lot of people and I'm sorry for the troubles your having now.

Tom

Re: C19 - Major Structural Issues - Progress

Posted: Thu Nov 30, 2017 3:54 am
by fallguy1000
Sorry if I was confusing at all.

Boat bottom has two sides - bilge and the exterior of the hull. Bilge where you had ingress and delam should be wetter than the opposite side where you used the other epoxy. If the readings are the same; you would be saturated. Not expected... "UP TOP" means bilge side.

The boat needs to test against itself so the readings from within the boat are all close. For example, the wet area of the bilge would test at say 18% on day one and a dry section forward tests at say 11% on day one and as you dry the boat down the dry area now tests at 10% and the bilge reads at 14%, you'll know you aren't ready to glass, for example. When the bilge where wetted reads 11% and the dry area reads 9%, you'll know you are getting closer to ready to repair. Ideal will be when the readings are the same. Those drier areas within the hull will help you understand if the areas that got wet are dried fully.

Tactially, running a fan and DH should work, but you ideally want to get the DH water out without opening the boat and adding the environment each time-hose run through drain of boat? Anothe gauge of things will be if the DH stops producing water. If you have the boat sealed off from the environment well with a fan and DH inside; you can collect the DH water in say a 5 gallon bucket and each day; it should produce less water down to the point it stops producing much of any. This, of course, assumes the DH isn't pulling from the environment, so you need to be sealed up pretty tight to get to zero water. The DH has the added benefit of heating the environment a bit, which is helpful in the drying process. You'd not need to add any other heat probably; just a fan to move air around. Air can stagnate badly in a boat bilge, so if you don't move air; you'll not dry through and through. Adding other heat can dry things faster, but too much heat can shut down the DH, and the DH produces its own heat.

Write down your initial meter readings and if you want to seal and bag the boat; you can use the DH bucket method and really monitor the drying without a lot of testing until it stops pulling water to your bucket. I would record the collected amounts and the times and you'll end up seeing a rate of removal that declines. Like one pint in 24 hours on day one, then 4 ounces on day 7, for example, to say zero water on day 14 (all guesses on my part). This method will also tell you if the DH you are using is working. Some DH won't work if they get too warm, so if you have water on day one and no water on day two, make sure the DH didn't stop running the condenser due to overheating.

If you have some good lamination, but it got wet under; that will rot in the future if you epoxy it in. I'm assuming you have some areas that didn't delaminate; so those areas will really need thorough drying if they wicked some water. I'd probably dry the boat with the DH method for about a week past the DH producing measurable water if it were my project. Those last teaspoons of water might come from the damndest impossible areas to dry. And the teaspoons of water can dry up in the collection pan in the right environment. So, the DH might be pulling from some laminated area with some water underneath and it won't seem important to you, but it will be. That will be the hardest part of the job-making sure you aren't enclosing any water where you have good laminate. Another reason I'd shoot for 8% is to ensure you dried up any areas with good laminate.

Mostly good luck.

Re: C19 - Major Structural Issues - Progress

Posted: Thu Nov 30, 2017 9:56 am
by TomTom
Got my new makita multitool today - remind me again why I have never used one up till now. What an awes Me bit of kit. Fully gets my thumbs up; even almost enjoyed hacking up my boat with it; so strangely addictive!!

Re: C19 - Major Structural Issues - Progress

Posted: Thu Nov 30, 2017 10:12 am
by Jaysen
Another one falls to the temptations of that SOB tool...

Bah!

Re: C19 - Major Structural Issues - Progress

Posted: Thu Nov 30, 2017 10:29 am
by fallguy1000
Jaysen wrote: Thu Nov 30, 2017 10:12 am Another one falls to the temptations of that SOB tool...

Bah!
Best thing since dried epoxy puddles on plastic for mind numbing pleasure.

Re: C19 - Major Structural Issues - Progress

Posted: Thu Nov 30, 2017 12:35 pm
by Fuzz
I am always finding uses for mine. Stuff I have no idea how I would have done without it. It and my Japanese pull saw get a lot of use boat building.

Re: C19 - Major Structural Issues - Progress

Posted: Sat Dec 02, 2017 12:52 pm
by TomTom
Well the new multitool did the job; one Makita plunge blade was used blunted but it did the job.

Seems that the right side was pretty firmly glued in.

Most issues on the Port as you can see in the first picture.

Image

Ground about a 3rd of the gunk away leaving the hull core/ 6mm plywood.

Image

Re: C19 - Major Structural Issues - Progress

Posted: Sat Dec 02, 2017 1:30 pm
by Fuzz
Man you got a ton of work done in a very short time :!: That thing is cleaned up very nicely. Now we will hope you do not find other problems. I am starting to think you have a shot at saving her :D

Re: C19 - Major Structural Issues - Progress

Posted: Sat Dec 02, 2017 3:25 pm
by TomTom
There is a whole lot less need to stop and stare idly at ones boat wondering if the console height or gunwale width or console position is ok when you are hacking you build up! I reckon I could dismantle a boat in close to Jacques estimated build times :lol: :lol:

Re: C19 - Major Structural Issues - Progress

Posted: Sat Dec 02, 2017 10:14 pm
by fallguy1000
Chicken or egg TT?

Looks like ingress from the bilge caused the forward port delamination.

Do be careful about trusting any of the side panels if they aren't accessible later.

Mostly good luck. It looks like things are drying up a bit already.

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 03, 2017 12:13 am
by TomTom
I will grind away all the paint and resin certainly till about 4 inches above where the sole was? Do you feel I need to go further than this?

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 03, 2017 6:51 am
by icelikkilinc
If it was me:
Since it is all open now, for my own peace of mind, I would have sanded down all side paint, not couple inches. If after measurements I decide that ply is still good, would fiberglass and start rebuilding from there.

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 03, 2017 7:41 am
by TomTom
You mean just on the inside; or sand the entire hull down?

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 03, 2017 12:10 pm
by fallguy1000
I would not worry about the outside; except for a moisture test and followup with repair of the pinholes.

I would be rather aggressive with inside sanding to make sure you don't have wicking or ingress anywhere else like the forward port section. Sand 4" up, but keep going if it looks dark underneath or any sign of delam.

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 03, 2017 5:20 pm
by icelikkilinc
Sand entire inside
If ply is good
Epoxy coat
Fiberglass per plans all interior
Than start building

If I had the same issue, I cannot live knowing there might be a hidden area.
Keep your chin up, you are doing great 👍

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 05, 2017 5:15 am
by TomTom
Thanks for all the support and help.

I think will be done sanding up to about 4 inches above the sole by end of the day/ tomorrow. All the laminations with tape and the fillets are rock hard.

Got quite a high reading on the moisture meter of 86% on one of the side panels; but it seems strange to me as this is above the sole, and to all intents and purposes, if one assumes that the chines are filled with thickened epoxy, and all the laminations were good, how could moisture have jumped to here?

I am debating routing a square of wood out of the bilge area (where I plan to put a shoot thru transducer anyways -if I rescue this sucker - so two birds one stone)... then ...

1) weighing it before and after drying in a dehumidified room - so I can sort of "calibrate" this moisture meter (it is a General MMD950)
2) I will have a "specimen" that I can keep an eye on
3) Expose some end grain to speed up drying

The moisture meter doesn't seem to have any wood/ plywood specific calibration. It is a pin and pinless combo. The pinless seems like total BS - it measures the end grain of plywood e.g. transom as relatively dry, but 2 inches along from the side it says its wet.

The pins seem a little better. Most bits of furniture around the house are about 16%; its humid here. About 7% in the dehumidified room.

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 05, 2017 6:19 am
by cape man
I would do #1 before trusting the meter.

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 05, 2017 2:49 pm
by fallguy1000
86 percent is probably a misread---

Follow my advice and wrap the boat with a DH with a hose running out the boat drain and run it for a day or two monitoring water with a 5 gallon bucket. Get a lot of water and keep on going.

I have not used the model meter you bought. I would expect MC readings of 30-50% in wet areas.

When you sample the boat; label the areas you pin test for rechecking and for repair as well. Document all readings well.

Do not glass the boat at 16%! Do not.

You can dry wood in a microwave. I forget the protocol, but there is online info. It only takes an hour to dry your sample that way. Just follow the method to avoid burning the wood or wrecking the microwave. I have done it, but forgot.

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 05, 2017 2:57 pm
by fallguy1000
The meter might be reading wrong on epoxied areas?

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 05, 2017 5:02 pm
by fallguy1000
okume/ply scraps?

Test them at ambient.

Soak one overnite;dry with rag and read it.

Learn to trust the meter.

Do another sample of just wetting the wood with a rag and get the reading, etc.

There is no cellular water in dried wood. You should not get 100% reading from the two I mention above, but the readings will help you understand how wet it wet.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Dec 06, 2017 2:00 am
by TomW1
TomTom use the pins. They will be more accurate. If you have spare wood out in your shop test it. I know you are in a humid area. So set up a base line. I don't know what caused the anomoly of 83% but I would not worry about it right now.

Tom

Re: C19 - Major Structural Issues - Progress

Posted: Wed Dec 06, 2017 6:17 am
by cape man
We regularly hit 95% humidity here, and i imagine you do too. That's why I'd test the meter in a controlled environment first.

Re: C19 - Major Structural Issues - Progress

Posted: Mon Dec 11, 2017 9:52 am
by TomTom
Well - I have sealed her under a plastic sheet and put a fan and dehumidifier inside.

It has been since Friday afternoon now; the moisture meter reading with the pins was showing between 8 and 11%; this is down from a sort of general average of closer to 20% and as high as 85% in some places.

I have checked the same pin holes and noted the readings so that it stays consistent.

About 5 lts of water have been caught in the jerry can that the hose outlet of the dehumidifier goes into.

I am cleaning up the stringers and putting them back in the hull to get the same treatment.

I guess the question is how long do I leave her like this for?

A part of me thinks its worth doing it for a long time - in case any rot "spores" are present - and hopefully time at low EMC will see them die off.

Another interesting thing is that the Relative Moisture - as measured with the Remote pinless probe shows that the bottom half of the boat (bottom panels and lower side panels) has less moisture than the top side panels.

This is interesting as it means that 1) the lower half is loosing moisture nicely, but 2) that somehow, the top side panels must be absorbing moisture over time.

I believe that this was epoxied properly - screw holes filled and drilled etc and this was done at a different time, so I am hazarding that the epoxy was good on that. It has biax on both sides.

This leads me to wonder if one can ever completely prevent moisture from at least reaching some sort of equilibrium within the wood?

For example, were I to completely seal my hull now, would it really remain at 8% ...?!

Image
Image

Re: C19 - Major Structural Issues - Progress

Posted: Mon Dec 11, 2017 11:51 am
by TomW1
TomTom wash down everything with a 10% solution of bleach. This is a standard sterilization solution Make sure you wear rubber gloves and a mask. So for 9 gallons of water add 1 gallon of bleach. That will kill any rot or mold spores that are hiding around. Wash every thing down and let it dry on the surface. Get on the underside of your frame also.

Tom

Re: C19 - Major Structural Issues - Progress

Posted: Mon Dec 11, 2017 1:34 pm
by TomTom
Ok thanks - great.

And that won't have any impact on the epoxy like my ethylene glycol idea (which by the way got totally kicked into touch by the Gurit Composites technologist?!
2) is it just unsuitable for over coating ethylene soaked (and dried) plywood.

Yes - it is unsuitable for coating / bonding / sheathing wood treated in this was - but then again so would all of our epoxies, or anyone's epoxies. Ethylene Glycol damages epoxies - so don't use it where epoxy will be used.


I hope this proves to be of help but let me know if you have any questions

Re: C19 - Major Structural Issues - Progress

Posted: Mon Dec 11, 2017 1:42 pm
by fallguy1000
If you are fully sealed; water should not be gained. If you have exposed wood; different story; perhaps catastrophic hydraulic erosion.

Bleach is not recommended by me. I don't care to argue about it. Stick with your antifreeze/borate plan. Borate is washing soda-you have it in Namibia almost for sure. I'd apply after you do a drying, scrape, vac; then redry it with dh.

Daily monitor water in the can. Once you get to a very nice dry boat; the can will be empty. The little bit of water leaving will dry in the lines.

Most likely you will reach a sort of exponential minimum, where the water production by the dh drops dramatically. Be patient and run for a few days extra because this is when you are really doing the best work; getting h2o out of nook n cranny.

This is all the same theory as drying lumber in many ways. In order to dry down further; it is required to heat the wood. I don't advise you bother. The dh should be raising the temp enough. But if you don't like the numbers; you could add a heat light; use caution for fire!!!!!!! A simple lamp would add heat even.

Don't test same pinholes. Check same area! The pinholes will dry faster!!!!!!! Never check same holes!!!!

It looks like you are going to save the boat.

I'm glad.

Rot does not die from low emc. Sorry; that is not how it works. Don't believe me? Post a question on gene wengert's woodweb.

All the best....you are turning a corner; be patient.

Re: C19 - Major Structural Issues - Progress

Posted: Mon Dec 11, 2017 1:45 pm
by fallguy1000
I see the antifreeze idea got a boot. I was a bit nervous about its greasiness.

I'd avoid bleach. It has been shown to do little. There are much better things to use. Perhaps the links you gave had borate only solutions if I recall.

See if Mr Wengert's forum has advice.

Dan

Re: C19 - Major Structural Issues - Progress

Posted: Mon Dec 11, 2017 1:47 pm
by fallguy1000
Just to add; each time you open the boat to test; you are adding environmental moisture; so toward the end; avoid the temptation to open the boat. You want to dh to pull from nook n cranny; not added damp air.

Re: C19 - Major Structural Issues - Progress

Posted: Mon Dec 11, 2017 10:49 pm
by TomW1
Bleach is absolutely necessary. Cracker Larry used it. I used it in my Green Houses. Hospitals use it. Nurses use it to sterilize the skin before giving you a shot, my wife and sister in law are both nurses and the old way is still the best way. Fallguy don't know where you got your info that it does little from but he needs to use it kill any spores that may be laying around. If he wants to do what you suggest then he can. Though in my opinion if the wood is solid I don't feel he needs to do so.

And no TomTom it will not have any effect on fiberglass or paint for that matter. It only kills the spores of the bad things you do not want or if there if there is any of the crud left in the wood that also. Put it on heavy and let it dry as I said above.

Tom

Re: C19 - Major Structural Issues - Progress

Posted: Mon Dec 11, 2017 11:20 pm
by Fuzz
I have no idea how to dry your boat but I am very impressed you were able to get the whole stringer grid out in one piece :!: That has to make your life easier when you go to put it back together.

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 12, 2017 4:23 am
by fallguy1000
I knew there would begin a great debate. Borates have been shown, as have commercial fungicides and antifreeze to perform better on s lacrymans than bleach. In most cases, bleach kills s lacrymans on the surface, but has a feeding effect deeper into the wood. Of course deeper in 6 or 9mm ply is another debate of its own.

This is well known in the commercial mold killing industry. Of course, I am connected to the industry by a relative; nothing more, but he says bleach is not used on wood as it doesn't kill down deep. A way to sell fungicides? Not sure.

Molds and s lacrymans are friends; so I found a source.

https://www.mold-answers.com/mold-removers.html

I am hopeful TomTom is not experiencing any deep wood rot. The borate solution would be my preferred choice based on other reading; zero personal experience. I have only used cpes on visible areas of rot we did not wish to remove.

But I am honest.

Bleach has another couple dings. First, when used in high concentrations; you need air supplied as it is too hot for humans. Second; bleach generally needs to be neutralized; I don't believe borates require it.

There is a place in the world that studies this in detail. Some Scottish college. Perhaps they hve a whitepaper on it, but it might be about timbers; not light plywood.

My preference would be the borate in solution.

I use fungicides a lot for killing turf diseases; most of them have boron in them. Another reason for the preference...

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 12, 2017 6:06 am
by cape man
Here in central Florida, where we get mild freezes (and sometimes hard ones!), a single light bulb under plastic draped over your favorite plant, generates a good deal of heat. Put one under that tarp and heat the air, which will make the DH work faster. Monitor it for several hours to make sure it isn't too hot.

I too was amazed by the pic of your stringers! That was awesome!

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 12, 2017 5:33 pm
by TomW1
Fallguy I ran/owned a Nursery for nearly 15 years. If there was something better than bleach I would have used it. My agricultural science unit never came up with anything better also. My main greenhouse was used for cuttings and made of benches of wood and stretched wire. We sterilized it every spring with bleach and never had any problem with mold or moss growth on the wood or more importantly the 30,000 cuttings we did. We sprayed closed the door and that was it never neutralized it. Starting cuttings is the most high humidity thing you can do as they must be misted constantly. Mist, evaporate, mist, controlled by a mechanical leaf.

Your post is for House Hold Cleansers, not commercial and I agree. Clorox still is a big name in house hold cleaners, go look at the grocery store.

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 12, 2017 6:17 pm
by Jaysen
There’s the part I’m missing.

What are we really talking about when we use the word “bleach”?

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 12, 2017 6:28 pm
by fallguy1000
Tomtom wants to kill any s lacrymans that might be alive in his hull before he epoxies it. It is anaerobic; so epoxy alone won't kill it. Cpes is an industry standard, but would cost an awful lot.

Me n TomW1 just have different preferences for how to kill it.

In the end; we both want for this guys boat to get fixed.

All a very friendly discussion. Believe it or not people can disagree and both be right.

I don't like bleach much cuz it burns my 👀

😭

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 12, 2017 6:54 pm
by TomW1
Jaysen wrote: Tue Dec 12, 2017 6:17 pm There’s the part I’m missing.

What are we really talking about when we use the word “bleach”?
It is the standard Clorox bleach out of the bottle. When used in the washer it may be 1/2 of 1% at 10% it is a universal sterilizer killing everything. At full strength it causes burns on skin and just is down right unpleasent.

Tom

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 12, 2017 7:03 pm
by Jaysen
Ok. So Clorox from the store. Are we concentrating it in anyway or are you saying it is full strength out of the bottle?

I’m asking because it doesn’t burn me when I use it. Not that I pour it on my arm for fun or anything but I often get it on me when cleaning things.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Dec 13, 2017 4:33 am
by TomTom
Thank you for all your responses and support.

For what it is worth, this was Gene from wood webs response ...
Rot or decay is only active and increases the amount of rot when the moisture is well over 22% MC. If you can seal the dry plywood and keep it sealed, there is no risk. The problem is keeping the seal perfect. If water gets beyond the seal, it is nearly impossible to get it out...the water is actually sealed in the wood.
This is what the guys at WoodCare say ...
Hi Tom,
Thanks for your email. We have a product called Bora-Care which is a very effective wood preservative. It is effective against all wood destroying organisms including fungal decay. It comes in a one gallon jug of concentrate. It is diluted 1:1 with hot water and either brush or spray applied. It works on damp or dry wood and will dry in a few days based on temperature etc. The slower it dries, the deeper it penetrates. Once dry, the wood surface can be coated with epoxy. We like System Three epoxies. Read and follow label instructions carefully. Thanks for reaching out.
Jim
This is what the Gurit tech says...
Hi Tom

If the epoxy coating is applied correctly - encapsulating the wood completely - then there is no requirement for a rot preventative.
We (Gurit) have not carried out any testing with proprietary rot preventatives but I have come across people using Borax but do not know the long term effects good or bad. But my feeling is just apply the epoxy well, let it do its stuff and repair any breaks in the coating / sheathing quickly and you will not have any problems. Lots of boats out there with "just" epoxy.

The timbers would have to be crusted in salt to stop the epoxy. Normal surface preparation should be enough to allow the epoxy to bond the the timbers. But it would be better if it where on there.

If the moisture levels do bounce back - flush her with water a few times and dry her gradually and I think you will be OK - it will just take time.
Note - the tech worried that the salt in the wood will make the moisture levels rise quickly once the dehumidifier is turned off due to its hydroscopic properties. So he says I may need to flush it with fresh water.

I would be very happy to simply epoxy coat everything - and I am going to put a cat amongst the pigeons here - but is epoxy really as good at sealing wood as we want to believe?

When I first started building epoxy-plywood stitch and glue boats, I was sold on the epoxies incredible ability to seal wood and make it innate. Its what we have all based our faith in these designs on.

However, the reality is that I have actually found this quite hard to achieve; and I now wonder if epoxy is more porous than I thought (or certainly my application of it!!!)

Take this current boat for instance. It is made with three plywood panels on each side - a hull panel, a lower side panel and an upper side panel that is epoxy glued to overlap with the lower side panel by 6 inches. 6 inches glued with thickened epoxy. The outside is sheathed in biaxial fabric and epoxy, as was the inside. All screw holes were overdrilled, filled with thicked epoxy and then redrilled. Essentially "watertight"...

My bad epoxy/ delamination issues were limited to the inside of the hull and to the bottom and lower side panels. I know this because that was all sheathed in one day, with one certain batch of epoxy. All the rest was a different brand and done at a different time.

The "bad bits" have been completely cleaned, sanded and scraped to bare wood and left under the tarp with a dehumidifier inside.

My pin moisture meter is telling me ambient here (I am in the tropics) is about 16%; but my hull and lower side panels are now down to about 8-11% under the trap and dehumidifier. (This is similar to test pieces I put in my dehumidified room in the house).

When I tested the hull with a Pinless sensor before I started dehumidifying it, it was telling me that the relative humidity was much higher in the lower side panels and the bottom panels; now it is telling me it is the other way round. At this stage this is good news - the dehumidifier is working and I am drying the bottom panels and side panels which had water ingress.

However, it is also telling me that the upper side panel - which is still "sealed" with fiberglass and epoxy on both sides and has intact paint - and which was built "up country" - in a place with a much lower humidity - has "quite" a high moisture content...

It is also telling me the spray rail - attached to the outside of the boat ontop of a layer of biaxial - is relatively "moist"...

So I begin to ask myself - how is the moisture content in these "sealed" parts so high?

Does the boat living at a higher ambient moisture mean that eventually water does diffuse through the epoxy?

And if so, can sealing the rest with epoxy - as best that I can - ever really be trusted to stop it reaching that 22% mark that might cause rot?

Re: C19 - Major Structural Issues - Progress

Posted: Wed Dec 13, 2017 5:43 am
by icelikkilinc
Hi Tom
In Turkey where there is a massive industry of wooden boat building, Gulet, Tirhandil etc..

These have been traditional builds and they have always used Wood Protective Impregnation Primers.

Nowadays they have started to migrate to never technologies. The boat is still wooden core but they started laminating fiberglass on wood on outside hull.
They use Wood Protective Impregnation Primer prior to epoxy / fiberglass process.
Actually they were quite surprised that I wasn't using one on my Tw28.
I have told that I was encapsulating my plywood core with epoxy prior to lamination.

I don't know if the same technique could be applied for a plywood core, just wanted to share what is used on a massive industry for boats ranging from 20M to 60M in length and spending their entire time on salt water.

example below, could not find more detailed pictures but in the 3 steps below, they use impregnation primers.

Image
Image
Image

After the veneer lamination as last layer, they but the final primer and than laminate fabric on water surfaces. example below.
They like the wooden look on other areas and keep varnishing those surfaces..

Image

not trying to hijack just a different perspective to what you last said...

Re: C19 - Major Structural Issues - Progress

Posted: Wed Dec 13, 2017 6:09 am
by TomTom
Thanks Ilker - great info - not hijacking at all -as you can probably tell I need all the help I can get!!

Out of interest why didn't you use the Impregnation primer on the TW28?

Do you know exactly what it is and where one can get it? Looks to me like if they are building huge projects like that they would know what works and what doesnt ?!

Re: C19 - Major Structural Issues - Progress

Posted: Wed Dec 13, 2017 6:23 am
by Jaysen
Wood is like a sponge. It will soak up water if. Epoxy is a barrier. It presents things getting to of from the wood. If you take a piece of wood at 8% moisture and sit it in a room with 80% moisture, the wood will gradually increase. The longer it is in the 80% environment the higher the moisture content will go until the wood is “saturated” and finds its equilibrium. If you then seal that wood in epoxy that moisture is trapped in the wood until the epoxy barrier if removed and the wood placed in a low humidity environment.

Solid wood will absorb more moisture than laminated vainer. Directly wetting wood will cause it to absorb more water than is sitting in humidity.

My gut tells me your issue is just a mix of bad luck and a “hostile” build environment.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Dec 13, 2017 6:41 am
by TomTom
Jaysen - my question is more that if I seal the wood (properly) at 8% - will the epoxy definitely prevent water from getting into it till it finds an equilibrium?

I know this may sound stupid but how waterproof is epoxy? I think it was the Gougeons Book I read somewhere that even epoxy isn't 100% water proof - just the best thing out there?

Re: C19 - Major Structural Issues - Progress

Posted: Wed Dec 13, 2017 7:10 am
by Jaysen
Waterproof is ALWAYS relative as it depends on 100% perfect coverage with no seams. Even they there is the porosity of the material. That said, on a technical level epoxy is waterproof. But that means it is up to the application to be perfect. You basically need to pre cut/drill every piece and then dip coat each piece to achieve that though. As in once you coat it you don’t penetrate the epoxy ever. Like with a moisture meter.

That is my understanding anyway.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Dec 13, 2017 7:16 am
by icelikkilinc
They have to use this primer on wood as Jaysen told, wood will act as sponge and soak up all the epoxy which will than cause delamination.

As example, on my bow, I have laminated a salvaged 10 cm thick solid wood with epoxy-wood floor.
Prior to glassing that, I have used this which my Epoxy supplier Duratek advised.
I have used the same method on my keel where I have lots of solid wood for added protection/ballast.
They are also the primary supplier to most boat yards in Turkey.
I believe it was product AV4560, it was been 8 years, the product code might have changed.

I have used this method on my TW28 where I used solid wood not on plywood.
on marine plywood, epoxy priming looked ok to me.
you could see the difference on wood vs plywood where wood was literally soaking up epoxy if not primed with this.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Dec 13, 2017 7:19 am
by fallguy1000
I would only use something if there were any areas of discoloration on the plywood when fully dry..

The point is mute if your plywood looks good. If your wood looks good; use some Clorox for a measure of certainty.

Not sure your laminating schedule, but for semantics, my designer said 10oz fabric and epoxy is not watertight. It takes a certain minimum. I believe he said 1208 was the lowest; however, this was for building watertight compartments with pressures coming up. I would say 6oz could easily get a wear spot in it, even when building and leave a spot for ingress.

The sides of the boat which are encapsulated in epoxy still had the ability to wick from the wet bottom, right?

Why would you expect them to be dry? I'd expect them to be the wettest as wicked water would be stuck there. Those are your nook and crannies I mentioned. That is why you need to dry the boat for several days beyond when you think it is dry and test with the meter. However, if you get odd readings, like say 15-25%, I'd probably grind out/sand off the epoxy so it isn't touching the pins. If the epoxy/glass has some conductance; you would get a false reading. I haven't tested pins in epoxy to see.

Epoxy is watertight, but not the stuff you used that didn't mix well and was thicker than molasses. You had a number of problems on the last build. First; you might have had high moisture content before glassing. Second, the wetout was poor (probably didn't get a bond to the wood in many places. Third, the mix was poor.

Be patient; things will work out well for you.

When you go to glass; not sure what these plywood guys do to avoid dry joint, but the main thing is don't be dry between glass and wood and repair any voids or bubbles after the epoxy dries.

For my build, I generally work in smaller areas and am either super wet so no worries, or I hot coat everything with cabosil and fast epoxy first. Then I have a tacky surface that is epoxied thoroughly. I don't think that is done on plywood, but perhaps prewetting. In order to prewet; I like to put sharpie lines on my dry fit glass, like chines or midpoints, so it is easy to lay glass on wetted surfaces.

I watched a couple of youtube videos of a guy who was befuddled as to why his epoxied boat was rotting from the inside out. Turns out he used some timber that wasn't dried and had to remove it all.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Dec 13, 2017 7:45 am
by Jaysen
From my early looking into epoxy over wood, the issue with glass being waterproof is that it is not “solid” allowing the epoxy to have gaps. If you used a thickened epoxy to wet (more like putty) the glass with a guaranteed continuous layer then it would be water tight.

As to primer, JM build methods uses straight epoxy to prime the wood. Same principle. Wet the wood to prevent leach of epoxy from glass into wood. I had a few “dry” areas that required two coats of pre sealing. As I figured out the process I learned how to combine the encapsulation and glassing to make things move along nicely.

All in all building a boat is simple. But the reality (as we can see In the repair threads) is that even pro shops struggle to get it right. Especially if the budget is driving the build.

I’m sure you’ll get this one licked. As the almighty cracker would say... build on!

Re: C19 - Major Structural Issues - Progress

Posted: Wed Dec 13, 2017 9:42 pm
by TomW1
TomTom the BoraCare sounds like a good thing for your bare wood. But for everything else I would use the bleach solution, to totally disinfect your boat. We just used a back pack sprayer to keep our distance from the actual spray and to get into every nook and cranny.

I really admire your perseverance on rebuilding your C19, keep up the good work.

Tom

Re: C19 - Major Structural Issues - Progress

Posted: Thu Dec 14, 2017 3:18 am
by Fuzz
TomW1 wrote: Wed Dec 13, 2017 9:42 pm
I really admire your perseverance on rebuilding your C19, keep up the good work.

Tom
Same goes for me.
It would be a crying shame if you are not able to save such a nice looking boat.

Re: C19 - Major Structural Issues - Progress

Posted: Thu Dec 14, 2017 5:46 am
by TomTom
Oh I think she will be good for a few more years - then I should probably sell her to someone who I don't like and start again!! :lol: :lol:

Definitely a learning curve.

The issues I am pondering right now are these:

1) do I wash her in fresh water to get the salt residues out - which are hygroscopic. I am truly deeply impressed with what a dehumidifier and plastic covering and a fan can do.
2) do I go with a bora care type treatment or not (would suck to have epoxy issues again because of either salt in the plywood or bora treatment - but would also suck to waste good epoxy and resin to seal in some rot!)
3) I also like Ilker's suggestions - of wood protective impregnation primers - but need to find out more on that subject.

Re: C19 - Major Structural Issues - Progress

Posted: Thu Dec 14, 2017 6:51 am
by Jaysen
1. Yes. Do it right even if it takes more time and you’ll have the piece of mind not enjoy the boat worry free.

2. I would. And then bleach. Belt. Suspenders. And duct tape. Nothing wrong with overkill at this point (unless it creates a chemical reaction that is extremely harmful). But then I’d was with water a few times. Aka #1.

3. Repeat of suggestion #2. If it gives you piece of mind do it.

Let me agree with others in admiring your efforts. I would have gotten a saw, some patrol and a match a while back. Stick to it and we will all cheer you on.

Re: C19 - Major Structural Issues - Progress

Posted: Thu Dec 14, 2017 8:54 am
by fallguy1000
Did you remove rot already?

Take some closeups of said if so.

Show them here.

We all like boat pics.

Re: C19 - Major Structural Issues - Progress

Posted: Thu Dec 14, 2017 9:31 am
by TomTom
Havent seen any rot... just being pre-cautious!

Re: C19 - Major Structural Issues - Progress

Posted: Thu Dec 14, 2017 1:28 pm
by fallguy1000
Dry it up well; it won't rot unless your hardwood was wet to start on the gunnels.

How much water ungettin each 24 hours?

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 17, 2017 12:03 pm
by TomTom
I haven’t looked recently - but was still getting a bit. I will start measuring every 24 hrs from tomorrow!!

Now for the question that I have been wrestling with in my head, but too fearlful to post on the forum!!

Do you guys think I would be mad to consider extending my hull by 10%.

Pros List

1) I have always wanted a bit more Fishing space
2) I think the boat will ride nicer - not that she doesn’t ride nicely already.
3) my new engine is a 150 4 stroke Yammie - that’s a lot heavier than the old FICHt 90; and being a fishing boat everyone likes to be at the back anyways.
4) I’ve never antifouled her - so a hull extension would be a good time to do this as well.
5) if ever there was a time to do it, it would be now! And maybe when it’s done I could say “wow - well it was all worth it for that!”

Cons list

1) risk throwing good money after bad - if hull not as sound as I hope

2) will take a fair bit more work to get her back in the water

3) risk taking a nice hull and turning it into something that doesn’t work well anymore

4) how much do I really gain from the extra effort.

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 17, 2017 12:37 pm
by cape man
Leaving that answer to Jacques! 8)

But now would indeed be the time.

By the way...applaud you drying everything out like you are, and certainly the right call, but if the plywood was compromised you would know it by now. Redo the glass with good epoxy and I think you are golden. I would bet that my plywood had "moisture" in it towards the end of both my builds just from the 90% humidity we have here. I fully understand your angst over this given what you found, but I don't think it was water intrusion as much as epoxy that never cured properly.

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 17, 2017 2:45 pm
by jacquesmm
It would be a lot of work but not impossible: one extra frame, extending the stringers and extending everything else but I am thinking of the structure first.

Capeman's comment about checking the plywood integrity is a very good point: you will know what you have there.

There will be a long overlap of fiberglass between the original hull and extension. The stringers and sole will be the backbone that keeps it together.

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 17, 2017 2:59 pm
by fallguy1000
Wouldn't it be easier to bracket the boat and put the OB out back 2 feet and pickup a little bit of space?

Just a thought; not sure if it is a JM approved idea.

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 17, 2017 4:21 pm
by TomW1
Fallguy brackets have been discussed on the C19 many times it is just to light and Jacques counsels against putting one on it. The LCG moves to far back with a bracket. Unless he's changed his mind over the last 7 or 8 years.

Tom

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 17, 2017 5:14 pm
by silentneko
Just for conversation, instead of a conventional bracket, what about a newer style floatation bracket? The ones they are using to offset the weight of 4-strokes on older hulls?

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 17, 2017 5:38 pm
by TomW1
They provide flotation at the dock but when on plane there is no flotation available. See http://www.armstrongnautical.com/brackets.htm

Tom

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 17, 2017 5:59 pm
by silentneko
I'm not following your theory on that, if you extend the hull bottom by mirroring it with a sealed bracket how could it not provide a positive offset?

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 17, 2017 7:28 pm
by reefie
My feeling on extending your hull given your current issues is that it my well be a better option to start from scratch and build a new sound boat to better suit your needs. However, I'm not saying that what you are doing in rescuing you current boat is wrong - I think you are on the right track here, but when you throw in a hull extension and all the associated work, I think this changes the equation considerably. Just my thoughts.

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 17, 2017 10:31 pm
by fallguy1000
I'm with Reefie.

Re: C19 - Major Structural Issues - Progress

Posted: Mon Dec 18, 2017 1:57 am
by BarraMan
Extend the hull? No, not for me.

If you want a bigger boat - build it.

Re: C19 - Major Structural Issues - Progress

Posted: Mon Dec 18, 2017 6:26 pm
by icelikkilinc
reefie wrote: Sun Dec 17, 2017 7:28 pm My feeling on extending your hull given your current issues is that it my well be a better option to start from scratch and build a new sound boat to better suit your needs. However, I'm not saying that what you are doing in rescuing you current boat is wrong - I think you are on the right track here, but when you throw in a hull extension and all the associated work, I think this changes the equation considerably. Just my thoughts.
leaving the romance of rescuing the old friend aside, I agree with Reefie and would build new rather than extend,

Re: C19 - Major Structural Issues - Progress

Posted: Mon Dec 18, 2017 6:38 pm
by jacquesmm
I replied based on the assumption that Tom did not want to build a new hull. However, building a stretched hull may be easier and because of the beam not changing, it will be possible to recycle many of the other parts.

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 19, 2017 1:38 am
by TomW1
Tom I would go ahead and go ahead and extend your C19 you already have all the expense of building it and it will only cost you a couple of thousand more to stretch it. You have built two boats and know what you are doing. So do what you want. I think you are really doing the right thing in drying out the right thing in drying out the inside and giving it a good treatment. Your outside is fine so just sand down to the wood so you can get a good fiberglass epoxy bond for the extension.

Tom

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 19, 2017 3:04 am
by Eric1
I'm with TomW1 on this. If you ever thought of extending your boat, now is the time. :wink:

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 19, 2017 6:25 am
by cape man
Whatever you decide, you're my hero for fixing her and posting all this for future builders.

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 19, 2017 2:39 pm
by TomTom
Doing circles in my head on this one!!

I think I have figured out how I would do it, if I did extend the hull...

Jacques, would you mind looking at my methodology...

1) Seal all the dried out plywood and fabric the inside of the hull as it is.
2) Glue the stringers back in - except for a foot or so from the transom - where I would cut the stringers off in a staggered fashion - two longer, two shorter.
3) Cut the Transom off and put it aside.
4) Bolt on my stinger extensions to the existing stringers - so they stick out the extra 2 feet beyond the back of the hull.
5) Temporarily attach the transom to the extended stringers.
6) Take out the middle side panel for say a foot or so in from the back of the transom - so now my hull has a full length (as the boat is now) top side panel, a shorter middle panel, and the full length hull bottom, plus stringers extending to the new length and the old transom temporarily in place. The front part of the hull (bar the rear 2 feet or so is fully solid and repaired (except for no sole) at this stage).
7) Flip the hull.
8} Extend the middle side panels to the new length, by gluing an extension up against the topside panel where the two panels normally overlap by 6 inches. I can now shave down the sides of my transom till the new extension fits well and the joint continues the old shape of the hull and is fair.
9) Now I can loft the bottom panels to fill the gap between the transom and the extended bottom side panel.
10) Cable ties, thickened epoxy, fillets, tape etc... Fabric... fairing compound, finish out side etc
11) Flip hull back over.
12) Unbolt my stringer extensions so that I can now glass this part of the hull and the joints
13) Glue and laminate in the stringer extensions
14) Continue with the rest ... foam, sole, etc...

Re: C19 - Major Structural Issues - Progress

Posted: Tue Dec 19, 2017 2:59 pm
by jacquesmm
The sequence looks fine but I would add:
The final stringer extensions overlap should be at least 2' or 60 cm.
The bottom seam will be a butt block about 30 cm long, less for the sides.
An extra bulkhead will be installed over the seam, over the butt block but I am not certain about the location. You could have your new motorwell bulkhead there and add a frame in front of it.

It will become clearer when we see the work in progress. I"ll keep watching your progress.

My biggest worry is to be certain that you start building on trustworthy material, be certain that there is not wet or partially cured material anywhere.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Dec 20, 2017 9:33 am
by fallguy1000
How are you going to keep from getting a wave in the hullsides? Surely the boat is not square, or is it square aft? Or don't you mind a wave?

The same question for the gunwhales.

Is your dh still making water?

Kind regards.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Dec 20, 2017 10:34 am
by jacquesmm
Please keep in mind my second to last post: I would prefer to see you building a new hull than extending. If you extend, I will help but there is a risk have a kink or a flat in the extended hull.

I have done it several times and only once did I not have a visible transition. I screwed a good number of long battens in the bottom and sides and used then to shape the extension. It is labor intensive, that is why I proposed to build a new longer hull.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Dec 20, 2017 10:44 am
by fallguy1000
jacquesmm wrote: Wed Dec 20, 2017 10:34 am Please keep in mind my second to last post: I would prefer to see you building a new hull than extending. If you extend, I will help but there is a risk have a kink or a flat in the extended hull.

I have done it several times and only once did I not have a visible transition. I screwed a good number of long battens in the bottom and sides and used then to shape the extension. It is labor intensive, that is why I proposed to build a new longer hull.
I think if you are going to do it; you'll have to be willing to allow some flaws in the final product. JM, here, reaffirms my 'question'.

Kind regards.

Re: C19 - Major Structural Issues - Progress

Posted: Thu Dec 21, 2017 11:37 pm
by TomTom
Jacques thanks - it’s not a foregone conclusion that I will extend -but I have to have something to think about while the dehumidifier runs!

1) Out of interest so u think if you had used the batten method on the hulls you extended that had flat spots, they would have come out ok?

2) If I am extending the hull at the back and I do end up not quite following the contours, what are the ride implications?

Re: C19 - Major Structural Issues - Progress

Posted: Fri Dec 22, 2017 12:06 pm
by jacquesmm
The battens system, if done right, produces a smooth extension. Think of it as a female mold.

The extension will move your center of planing lift back but you also move the engine and batteries. I would not even move the console, just re-arrange the weights.

Re: C19 - Major Structural Issues - Progress

Posted: Fri Dec 22, 2017 2:05 pm
by fallguy1000
Can I ask a dumb question?

Why can’t you just cut the end of the boat off transom n all say at your aft intersection? Or is that what is done?

For the female battens; do you have to put screwholes on the outside of the hull and repair?

Just curious.

Good luck!🍀

Re: C19 - Major Structural Issues - Progress

Posted: Fri Dec 22, 2017 4:37 pm
by jacquesmm
For the battens: yes, you have to drill in the hull. You can limit the drilling by strapping the battens around the hull.

BTW, I would cut the transom off, extend and install the transom boards back in between the hull panels but again, to do that right may require more work than to build a new longer hull from scratch.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 5:16 am
by TomTom
Happy New Years everyone - I wish you all a wonderful 2018.

My re-build and lengthening of my C19 - "Auspicious" - has gone very well, and despite slightly going over the designers 10% recommendation, I am very pleased with the results.

Image


:lol: :lol: :lol: :lol:

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 9:19 am
by cape man
Amazing work !

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 9:42 am
by pee wee
Looks pretty good, but I can see that lump in the hull where you spliced the new part on. :lol:

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 9:59 am
by TomTom
Ive ordered a few liters of Quick Fair

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 10:49 am
by Jeff
Nice!! Jeff

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 11:36 am
by fallguy1000
Thanks for the laugh TT!

Neither of us want the fuel bill of that beast.

I did some checking. It is a Viking 80’ for those interested in pursuing her.

A Marlin lover’s dream charter.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 12:10 pm
by TomTom
Yeah - I would hate to see that fuel bill!

Jokes aside though the thought of extending Auspicious is still burning holes in my brain... and seeing as it will take some time for my plywood to arrive I can keep toying with the idea.

I don't think that I am intimidated by the idea of getting it to not look like it was extended - I have been looking at the lines and thinking about battens etc and I think I could do it without it looking like a catastrophe.

So really my thoughts are more about whether it is worth the effort/risk and what - if any improvements I will see.

I know I have brought this up before, but if I extended her by 2 feet - I would have a 21 foot hull - which in theory is now long enough for a transom bracket. If I added a bracket I would gain 4 feet of usable cockpit space.

Next thought - would this be like increasing my waterline length by 4 feet at displacement speeds? - and what differences would I see at trolling speeds? I know on the plane I would still basically have a 21 foot hull, but with the whole hull in the water would she be like a longer boat.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 12:55 pm
by silentneko
From what I remember the sides of the c19 flatten out more or less towards the rear, so extending it to where it looks ok shouldn't be impossible. I've seen guys use battens from the outside and inside to extend hulls, but it can't be a hull that curves a lot.

Why do you think a hull needs to be at least 21ft to put a bracket on?

Another option could be to extend the hull into a swim platform/built in bracket. It would give you a matched running surface, but push the outboard back out of the way.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 2:18 pm
by TomW1
Tom I think your on the right course. First I would use a wood butt block on the inside to align the extension and provide extra strength. Then I would use a fiberglass splice on the outside. You could inset this to provide a clean no line seam. As far as the bracket sure but you will want to make it a full width one and one that adds buoyancy at rest like an Armstrong. {Stileenko Jacques boats are to light for brackets on boats much under 21',this hasbeen discussed many times before.}

Tom if you go with a bracket you will need the transom bulkhead but you can move it back to only 10-12" from the transom and then install the motor well sides.

Armstrong Brackets at: http://www.armstrongnautical.com/brackets.htm

Tom

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 2:33 pm
by TomTom
I suspect I know Jacques answer to this - but would it be possible to make an integrated bracket by extending the stringers through the transom.

I know he will not have anything to do with people making their own "bolt on brackets" - was wondering if this also applied to ones where the stringers were projected through the transom?

My other concern with a standard bolt on Armstrong is how much more strain it puts on the hull and whether I will need to reinforce/ add biaxial to account for this.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 3:05 pm
by fallguy1000
I have wondered why JM hasn’t dabbled in the area of integral brackets. There is certainly some learning required for the NA.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 3:35 pm
by TomW1
Fallguy he has stated before that it is liability issue and he does not want to get involved with them. He keeps to what he knows. :D Any update on your Skoota it has been a couple of weeks. :?:

Tom what HP motor are you putting on the extended boat. I forget what you had on the C19 are you using that motor?

Normally Jacques will say no on larger HP motors to extending the stringers. The transom is always over designed so it will handle the bracket as it will be bolted across the width of the bracket.

Let's see what Jacques says.

Tom

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 3:55 pm
by TomTom
150 HP 4 stroke Yammy; had a Ficht Ram 90 before

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 4:09 pm
by silentneko
I can definitely see him shying away from liability on guys building their own bolt on brackets. A fully integrated one though I'm betting not many have asked for, but may in the future.

When you think about it, since the stringers, hull bottom, and sides run all the way back there, it can have all the support it needs. It's just a change in the shear height for the last few feet.

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 4:17 pm
by TomW1
Ok I remember the Ficht 90 glad you moved up to the Yammi 150. The transom will fine with it bracket or not. If you want put a layer of Fg on the inside and outside.

How's the wood moisture readings going. When I am working with cabinets I want a reading of about 10-15% You don't need to go any lower that that. If you have a constant reading below 15% your good. I have worked wood for 50 years learned from my granddad and dad. Wood varies by location and season. It cannot be controled by you unless you have a huge climate controled building. Your always going to be on the high end of the reading becuase of where you are but don't worry about it. Do a test of scrap if you think it will do you any good.

Tom

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 4:31 pm
by Fuzz
DayTrip, Mbiggerstaff and myself are all doing, or have done, a bracket by extending the stringers. I need to look back and see if DayTrip did his this way and see how it worked out. As for me I knew from the start I was on my own and accept this. I completely understand why JM does not want to get into this. I hope to learn how mine works out some time this summer. If you add a bracket I would expect to be on your own but I would enjoy seeing it done and learning how it all turns out :wink:

Re: C19 - Major Structural Issues - Progress

Posted: Wed Jan 03, 2018 8:00 pm
by fallguy1000
Slow, putzy bottom work on the Skoota.

I will update later tonight or tomorrow, but pretty boring to be honest.

TomTom-see if mbiggerstaff or one of these guys who succeeded will give you a consult.

Re: C19 - Major Structural Issues - Progress

Posted: Fri Jan 05, 2018 3:13 am
by TomTom
Mositure readings are sitting in the 8-10% range.

I have been doing some experiments and when I take a piece of plywood out of the dehumidified store, it gets to about 15% moisture from this in about an hour!

Possibly this is just on the outside layers.

I will have to figure out how to work fast once I decide to seal the hull again.

What is the general consensus on how much improvement I might see at 8 knot trolling speeds (in terms of efficiency) if I added 2 feet and the right transom bracket (bought bolt on or otherwise aside) ?

Re: C19 - Major Structural Issues - Progress

Posted: Fri Jan 05, 2018 2:44 pm
by Fuzz
To my way of thinking if you go with a bracket that is bolt on style it will not help and could even slow you down. I do not see them as making your waterline longer just something more you are dragging through the water. But this is just my gut feeling for what that is worth.

Re: C19 - Major Structural Issues - Progress

Posted: Fri Jan 05, 2018 5:30 pm
by TomW1
TomTom sounds like your ready to go. How sound is the surface of the plywood or is it fine or do you need to sand it to get a nice surface.

As far as the bracket like an Armstrong they attach to the hull and rise up from the boat to the end of them. So at rest and slow speed they provide positive flotation. When on plane they are completely out of the water. So while it adds 2' of length since it angles up you do not get the full benefit of a straight hull addition.

So in reality you get some help at trolling speed but not as much as you would expect.

Tom

Re: C19 - Major Structural Issues - Progress

Posted: Fri Jan 05, 2018 10:17 pm
by fallguy1000
TomTom wrote: Fri Jan 05, 2018 3:13 am Mositure readings are sitting in the 8-10% range.

I have been doing some experiments and when I take a piece of plywood out of the dehumidified store, it gets to about 15% moisture from this in about an hour!

Possibly this is just on the outside layers.

I will have to figure out how to work fast once I decide to seal the hull again.

What is the general consensus on how much improvement I might see at 8 knot trolling speeds (in terms of efficiency) if I added 2 feet and the right transom bracket (bought bolt on or otherwise aside) ?
I say none. You just get interior space at the exchange of increased wetted surface and probably a bit poorer performance for a bigger boat.

Don't stress out too much about the humidity. No reason to undo a nice dry boat. If you can keep it dry before you seal it up and during; go for it. If it is too much trouble, I'd not worry.

Your goal is for minimal production from the DH. Once the DH is producing only a minimal amount of moisture; it is probably just from leaks in your cover. However, the DH is probably raising the temperature under the cover, so most likely no condensation would occur and very little cold, damp air would ever migrate into the enclosure.

I like your numbers, but the water production is the real story. How much water are you getting each day now?

Re: C19 - Major Structural Issues - Progress

Posted: Sat Jan 06, 2018 1:03 pm
by TomTom
The wood is very dry; I can just tell that - it’s crisp and brittle; I used to build wooden longbows and that was what we looked for.

The machine still produces a couple litres a day; but I think that is just from the humid air more than anything.

In fact took the cover off today - to finish cleaning up a few spots and to see how much the moisture bounces back.

Have been running lots of experiments.

Basically getting close to sealing it all off and putting it back together.

Re: C19 - Major Structural Issues - Progress

Posted: Sat Jan 06, 2018 7:41 pm
by fallguy1000
A couple litres is a lot.

I am not sure how well you are sealed, but I would think a pint of water or less per day would be your goal. Although if you have a dry environment; nature will make it wetter.

If you had 1/8 of plywood saturated at 100%; you’d have 14 gallons of water to remove at 180 square feet. Ugly assumptions,

You need to make a notebook and keep track of your production because while my 14 gallon number is high; you have an idea.

If you production drops to a constant; you are probably only pulling outside air.

Re: C19 - Major Structural Issues - Progress

Posted: Sun Jan 07, 2018 4:31 am
by TomW1
Fallguy he is ready to build, the misture tests on his wood are fine. Forget the DH it is just picking up out side air humidity. See his previous post.

Tom

Re: C19 - Major Structural Issues - Progress

Posted: Thu Jan 11, 2018 11:05 am
by TomTom
Ok I know you guys like pictures - so here we go.

I have flushed the boat twice with freshwater to try and get any "hydroscopic" salt residue out (this was at the advice of the amazingly helpful Gurit technician).

I have ground away everything that could possibly constitute grime or dirt - and I have even scraped along the top edge of the bottom panels so that I can make sure this gets a proper epoxy coating.

I am pretty sure that I am not going to extend the hull... I suspect that it will cause the project to drag on forever... and from what I gather a leopard doesn't change its spots = I am never going to get this hull to be particularly efficient at 8 kts - which is what I would really like out of a boat - so I guess it means that one day I will have to build another; and whilst I do that it will be nice to have one to use! By then everyone may have forgotten I had to gut it and maybe I can even sell it!!

I do have a couple of questions for Jacques...

1) I know that it is generally ill advised to have a boat without a motor well - but I have raised the transom 5 inches to 25" and I have never felt uncomfortable with the boat as it was - could one put this boat back together without the motor well/ and bulkhead (just have it as a frame) - and if so what would have to happen to the lamination schedule to make sure the transom is strong enough (without the transom knees etc)?

2) Where approximately in this hull is the center of lift - I am trying to figure out how much weight and balance difference I will get if I put an 80 lt. fuel tank in the stringers in front of the console between the 2nd and third frames from the front?

3) With the frames above the sole - I often stubbed my toes on them - and I really found fairing between them a pain in the rear - could one use a larger/ squarer frame instead of the 9mm x 3" x biaxial taped frames? I was thinking something along the lines of a 2"x2" - epoxy glued but not taped (above the sole only)...

Image

Re: C19 - Major Structural Issues - Progress

Posted: Thu Jan 11, 2018 11:44 am
by terrulian
I probably missed something here but why are you interested in efficiency at 8 knots in particular?
Wouldn't that be in the transition zone between displacement and planing modes, where all boats exhibit their lowest efficiency?

Re: C19 - Major Structural Issues - Progress

Posted: Thu Jan 11, 2018 12:41 pm
by Browndog
It sounds like he is looking for a boat to do high speed trolling for Tuna, wahoo and other high speed pelagic species.

Tom, I would think that any of the boats that Jacques designs that have a V up front and a relatively flat bottom near the transom would do well in this role. You might sacrifice some rough water handling to get the high speed trolling efficiency. The C19 I believe has a deeper V at the transom and is probably great for traveling in a head sea for it’s size.

I’m curious about the GS28, especially with the Carolina flare option and outboard bracket. Isn’t your buddy building a GS28? The CS23/25 or PG25 that other guys have built look good and you could get some real world performance numbers from them. Any of those seem to be good choices for a future build.

Re: C19 - Major Structural Issues - Progress

Posted: Thu Jan 11, 2018 1:23 pm
by TomTom
Wouldn't that be in the transition zone between displacement and planing modes, where all boats exhibit their lowest efficiency?
Yes - I think that in general you are absolutely right - particularly if you look at the average power boat sold to the American consumer as a "Center Console Fishing boat"... all the gear, live-wells, bait-wells, toilet, 17 rod holders, 3 hot blonde chicks in pink Bikinis on the front (these are added and generally very expensive accessories), in-floor cool boxes, an ice-maker, a jacuzzi etc squeezed into a boat that you can tow home. It is advertised as having a really high top speed, an amazingly smooth ride and some sort of special patent hull that does all sorts of things that no other boat designer or manufacturer ever thought possible!!

But the reality is that all these boats are simply a constant deadrise, planing hull... with frills.

When I was younger and didn't know better, I used to page through old Bass-Pro shop or similar magazines, just drooling with envy at the latest Mako or Sea-Craft...(and the bikinis) ... available in America and thinking - now thats what a fishing boat should look like!!

Now I am a little older and hopefully a tiny bit wiser, I often wonder what has driv
en this - did the needs of the fisherman drive the design, or did the advertising drive the frenzy that made guys like me think this is the go to "fishing boat" of choice...

I am sure where one lives, the type of fishing one does, how much free-time one gets, gas prices and what your political views are, also drive this massively ...

So lets say you live say in Florida, fish in the flats, only have one day off a week and run hard and long distances between fishing spots. You live in a great country where gas is relatively cheap (and used to be dirt cheap and in a state where the neighbors don't mind how much gas you burn on the weekend) and then you spend most of your time either drifting, poling, bait fishing etc - with the engine off or running at displacement speeds, then the "pure planing hull" makes sense...

But let us say that you live somewhere where you fish off-shore, but most of the fishing you do is trolling marlin/ sailfish lures at between 6 and 9 kts, the run to the fishing grounds is only a few miles, and it is uncomfortable/wet/ possibly dangerous/ bad for your boat to go anywhere over about 17 kts anyways. You have to carry jerry cans of fuel onto the boat as there is no dock gas station and the fuel is relatively pricey. In this case, this kind of hull doesn't actually make that much sense.

In a whole day fishing here, you might spend maybe half an hour running out and half an hour back - and the rest of the day trying to attain a speed that the boat just plain (pun intended) wasn't made to do... and yet the difference between pulling a lure at say 5.5 kts (hull speed) and 7 kts can be the difference between a great days fishing and getting skunked...

If I choose to livebait small bonito for marlin at say 4 kts - I can get away with 45 lts of fuel in a days fishing; if I pull lures for Blue Marlin at 7 kts I will burn 110 lts minimum.

Of course - none of this I knew before I built my C19.

Don't get me wrong - it is (was) a great boat, that did everything that Jaques said it would; but at the time I built it, I probably didn't understand my use enough; or my use has changed... I used to like water-skiing as well as fishing ...

I also didn't realize (and still do not really understand whatever clever trick the designer employs to achieve it) this sort of hull type that I believe is called a "warped plane" or "variable deadrise". Anyone wanting to give me a good/better explanation of exactly what this is and how it is achieved please, please do so, I would so appreciate it, because I believe it is quite subtle and yet, the difference can be remarkable.

But essentially these hulls operate better at these moderate speeds between planing and displacement. I believe that hulls in the C19 size/ length/ shape range that would do better at these speeds would be the FS19 and with the same sort of shape the Novi 23 and DE 23...

You can then improve on this with a longer skinnier hull - and that where the Panga's and the GS28 come into their own...

And then of course, there is just the plane fact of building your boat lighter...

Re: C19 - Major Structural Issues - Progress

Posted: Thu Jan 11, 2018 1:24 pm
by TomTom
Sorry Browndog - I didn't see your post - but you hit the nail on the head.

Re: C19 - Major Structural Issues - Progress

Posted: Thu Jan 11, 2018 1:57 pm
by terrulian
Very thorough answer. Thanks for taking the time. :D

Re: C19 - Major Structural Issues - Progress

Posted: Thu Jan 11, 2018 2:21 pm
by jacquesmm
TomTom wrote: Thu Jan 11, 2018 11:05 am
I do have a couple of questions for Jacques...

1) I know that it is generally ill advised to have a boat without a motor well - but I have raised the transom 5 inches to 25" and I have never felt uncomfortable with the boat as it was -
That is up to you but yu know the boat and it should be safe. I like the motorwell bulkhead as a safety feature.

could one put this boat back together without the motor well/ and bulkhead (just have it as a frame) -
I am not certain that I understand but if you keep bulkhead in front of the transom and the lengthwise frames, the ones used as MW sides, the answer is yes. I count very much on those longitudinal frames to act as transom knees. They could be replaced by raised stringers.

and if so what would have to happen to the lamination schedule to make sure the transom is strong enough (without the transom knees etc)?
You need some knees, you can't count on just the transom, we need some kind of box there. Same lamination schedule as before anyway.

2) Where approximately in this hull is the center of lift - I am trying to figure out how much weight and balance difference I will get if I put an 80 lt. fuel tank in the stringers in front of the console between the 2nd and third frames from the front?
Put it at 41 or 42% of the waterline, measured from the transom.

3) With the frames above the sole - I often stubbed my toes on them - and I really found fairing between them a pain in the rear - could one use a larger/ squarer frame instead of the 9mm x 3" x biaxial taped frames? I was thinking something along the lines of a 2"x2" - epoxy glued but not taped (above the sole only)...
Yes, a wider stiffener could work. I specified that on the rebuilding of the 23' Seacraft:
Image
A box that you also use to route wiring, fuel, vents etc.

Re: C19 - Major Structural Issues - Progress

Posted: Thu Jan 11, 2018 2:46 pm
by fallguy1000
What motor are you running? Maybe Tom can help you get the right speed via propeller mods at a small tradeoff for hole/top end. Also, I use a trolling plate here with a 45 degree angle mod.

I wish my motor has a fine tune for trolling speeds; some do have such a thing. For a few hundred bucks; seems the outboard designers could have a fine throttle adjustment for us.

As for trolling speeds, here we run between 1.5 and 2.5 mph-it is very tricky to dial in. Some days I run the plate down all the way if winds are behind me; that way I retain torque at low speeds. When speeds are higher; trolling down 160 feet gets tricky, too; near impossible in much wind.

Re: C19 - Major Structural Issues - Progress

Posted: Thu Jan 11, 2018 4:17 pm
by TomTom
Jacques -
could one put this boat back together without the motor well/ and bulkhead (just have it as a frame) -

I am not certain that I understand but if you keep bulkhead in front of the transom and the lengthwise frames, the ones used as MW sides, the answer is yes. I count very much on those longitudinal frames to act as transom knees. They could be replaced by raised stringers.
What I mean is turn the motor well bulkhead into a simple frame.

But if you are saying I need the transom/knees/box structure, I guess this would be difficult to do?

Could I instead move the bulkhead back further than shown in the plans - making the motor well smaller? I was thinking I could then make a removable cut out for when I want to trim the engine up; but that is in place with the engine down?
Yes, a wider stiffener could work. I specified that on the rebuilding of the 23' Seacraft:
My aim here was to do away with having to tape the frames - so if I had a wider piece with more surface area to glue and contact the hull panels I could do without the tape.

Re: C19 - Major Structural Issues - Progress

Posted: Thu Jan 11, 2018 4:32 pm
by jacquesmm
You need a bulkhead in front of the transom but it can be much closer than the MW bulkhead. It can be located at 8" (20 cm) in front of the transom. It should have a pair of vertical stiffeners tabbed between the transom and that bulkhead.
In the hulls with a full transom for a bracket, I shows such a frame.

Alos, since you lengthen the hull, you must add a frame. Try to have a frame each 38" (every meter) or closer.

Noe that a bulkhead is a full or almost full frame while a frame is just a contour, a ring.

Re: C19 - Major Structural Issues - Progress

Posted: Mon Jan 15, 2018 8:08 am
by TomTom
Hi Jacques - I think you missed the part where I said that I won't lengthen the hull!!

1) Can the motor well bulkhead above the sole be moved further back than the corresponding frame beneath the sole? or must they move together?

2) I am not sure if you understood, can I use say a 2"x2" piece of dimensional lumber - with no taping - instead of the frames with biaxial tape above the sole as you specify.

Re: C19 - Major Structural Issues - Progress

Posted: Mon Jan 15, 2018 1:06 pm
by jacquesmm
TomTom wrote: Mon Jan 15, 2018 8:08 am Hi Jacques - I think you missed the part where I said that I won't lengthen the hull!!
Sorry. We went back and forth about that and since I follow the building of many boats at the same time, I may forget what decision was made.

1) Can the motor well bulkhead above the sole be moved further back than the corresponding frame beneath the sole? or must they move together?
No need to move the floor frame (the one under the sole).

2) I am not sure if you understood, can I use say a 2"x2" piece of dimensional lumber - with no taping - instead of the frames with biaxial tape above the sole as you specify.
No, I did not get that. Yes, you can use a 2x4.

Re: C19 - Major Structural Issues - Progress

Posted: Fri Jan 19, 2018 4:12 am
by TomTom
I started to fiberglass my hull back together - but am worried that my fabric looks too dry when cured…

I have attached a few pictures of where I have laminated the 400 gsm biaxial fabric - which is 5 years old - has been kept on a roll, wrapped in plastic, in a store, but in an area in the tropics with a high ambient moisture content.

My work cycle was to heat the plywood of the boat slightly with a heat gun, to aid it in absorbing resin - and then to roll epoxy on with a foam roller. Wait about 15 minutes and then roll another coat over this and lay up the biaxial fabric on top of this.

I then used a foam roller to roll resin on top of the fabric. After this, I used a hard aluminum roller with ridges (as used in the fiberglass boat industry) to really try and squeeze all this in.

I am conscious that the aim of a good lamination is to try for an epoxy glass ratio of 50-50% and I am wondering if perhaps I have been too miserly with my resin… or whether the plywood (being extra dry from living under a tarp with a dehumidifier) is sucking the resin out of the fabric?

I also attach a photo - it hasn’t cured yet of a test sample that I gave done - I wetted the fabric with a brush this time.

The fabrics involved are:

1) a piece of 400 gsm biaxial that has sat in the dehumidified room
2) a piece of the same 400 gsm biaxial that wasn’t in the dehumidified room
3) a different piece of heavy 750 gsm biaxial that is about 10 years old
4) an 86 gsm woven
5) an piece of 126 gsm woven
6) a different batch of older 400 gsm biaxial.

As one can see, they all seem to have wetted out!

Would the smart move be to remove the “dry” laminates and start again?

Many thanks

Tom

Pictures below…

First 3 are in the boat; last 4 are of the (still wet) test sample which I thought I would do to rule out any issues with the biaxial - I thought it might be too moist - or perhaps was not compatible with epoxy? As you can see though,

all seem to be “wetted out”...



Image
Image
Image
Image
Image

Re: C19 - Major Structural Issues - Progress

Posted: Fri Jan 19, 2018 12:17 pm
by fallguy1000
too miserly with the resin Tom; sorry, but your guess is correct unless the resin is cold

this is EXACTLY what my 18 oz looks like if I don't have quite enough resin to finish

the easiest way to wetout the glass is by using plenty of epoxy UNDER the glass; your reroll should be very wet, 3/8" nap roller

My wetout rate for hand lamination is 120%, but this is for foam; ply might require more for the plywetout; if you want the wetout rate to be less; use peelply; the excess rises up into it

I see little value in heating the plywood; it can't retain the heat. What temperature are you operating in? Wetout is extremely difficult at temperatures below 16 C or 60F. The viscosity of the resin; not the temp of the substrate is the issue. Cold resin will not flow into the fibers in the fabric and your matrix will be dry.

It isn't viscous enough to penetrate the fabric well. Keep the resin at room temperature; it can be warmer than the substrate

the only testing of the glass that is old would be for brittleness, move it back and forth and make sure it doesn't break on mechanical fatigue

great post, by the way, sorry it doesn't look right to me at all, I have a bubble buster roller that I love for this, but you need enough epoxy first

Re: C19 - Major Structural Issues - Progress

Posted: Fri Jan 19, 2018 12:20 pm
by jacquesmm
I agree, it looks like it is not completely wet, starving for resin.

Re: C19 - Major Structural Issues - Progress

Posted: Sat Jan 20, 2018 11:29 am
by TomTom
So would you grind it all off and start again?!!

Some of the white is I believe from a thickened epoxy and wood flour paste that I used to fill some voids created by pulling up the old cloth!

I have also heard that the sizing used to hold Fiberglass fabrics together had a shelf life?

I did do a test on a larger patch and used way way too much epoxy and it came out nice and clear

Re: C19 - Major Structural Issues - Progress

Posted: Sat Jan 20, 2018 2:16 pm
by fallguy1000
We have no idea how big an area you did poorly.

But it looks like a poor wetout and I already assumed the stark white area was filler.

Start sanding and see what the bond looks like. It will be dry.

Sorry man.

Re: C19 - Major Structural Issues - Progress

Posted: Sat Jan 20, 2018 2:23 pm
by fallguy1000
This is the thing Tom.

It is dry. Your test proves it; you know it.

When you do the wetout; weigh or calc the glass and multiply by 120%.

Adjust usage from there. I use 2 rollers for wetout. A 3/8 paint roller and a bubble buster. The bubble buster does NOT move epoxy. It just helps with any stubborn areas, but there must be enough epoxy first.

Re: C19 - Major Structural Issues - Progress

Posted: Sun Jan 21, 2018 1:08 am
by TomTom
How much have I done - enough to not want to have to undo it - but in the grand scheme of things not enough to close my eyes and carry on if it is likely to cause problems down the line.

The Gurit tech reckons that the sizing in fabrics over about 2 years old start to break down and make them harder to absorb resin; and there I was thinking my 80 yard roll of biaxial would last forever! Man this has been a steep learning curve; and you would think that I should know better by now!

The heat gun has been recommended by some as a way to prevent outgassing - so you heat the wood slightly and apply the resin - as the wood cools it pulls the epoxy into it - not the other way round.

I guess my mistake was to try and keep my glass/resin ratio reasonable - I know I used way way more epoxy then the BOM last time I did this! No good deed going unpunished right now!!

Re: C19 - Major Structural Issues - Progress

Posted: Sun Jan 21, 2018 6:58 am
by cape man
Can you take a pic further out so we can see the wider picture? How much is starved cloth versus filler making it look white?

Re: C19 - Major Structural Issues - Progress

Posted: Sun Jan 21, 2018 12:25 pm
by TomTom
Image

This is the widest pic I have - I guess I got about a quarter of the hull done; it certainly seemed saturated when I did it - before drying; so I really am struggling to know exactly how much is white from the filler vs weave.

I also did a fill coat on the weave when it was still tacky.

I definitely don't think it will peel off - but maybe a bit of grinding will confirm that!!

Re: C19 - Major Structural Issues - Progress

Posted: Sun Jan 21, 2018 6:45 pm
by fallguy1000
Yes, this is an incomplete wetout for sure. The red sizing lines/stitching lines are not an issue; don't worry about them.

I circled a few spots that look REALLY, REALLY bad, but the entire job is rather dry looking.

If it was on the outside of the hull, I would absolutely say grind it all off.

You should be really careful and check a few areas to see if they bonded well enough (like the ones I circled). Then, after assessing the bond, I would fill coat epoxy just because the last thing you want is water ingress due to your lousy wetout.

It is too bad you did so much. Try slowing down a bit; you'll end up with better results and the costs are low. (lesson to myself as well)
tomtomsboat.jpg

Re: C19 - Major Structural Issues - Progress

Posted: Wed May 16, 2018 8:59 am
by TomTom
Image

So this is the progress on repairing my C19 -

1) I ran the dehumidifier till the moisture meter was showing 8% and then I sealed the plywood and sheathed it - and I also used peel ply - which you can see in the picture.

2) I have put the stringers back in and will peel away the relevant area of peel ply when I glass the frames back into place.

3) I have doubled the surface area of my cleats by using cypress 2"x2" split diagonally; I will glue these onto the wet glass when I do each section in biaxial.

4) I am doing away with chase tubes... everything will run down the center... which will have a removable floor for access... I am done with trying to make sure PVC chase tubes are water tight where they join the sole.

5) I am now planning whether to use PU foam or Expanded Polystyrene blocks in the sealed compartments. I am totally over dealing with water under the sole - but I am not convinced one can ever be fully convinced that it will never get in... I only have to think of Matts DE25 and I cringe.

I am skeptical that PU foam doesn't absorb water over time if water is in there - and furthermore, I worry that one cannot drain compartments that ge t water in them without a major rebuild ... which I don't want to do again...ever ever ever...

So I am thinking that if I have blocks of Expanded Polystyrene in each compartment filling them up and reducing the volume if I have a catastrophe, so the boat wont sink, I can still have a series of limber holes between the frames to strategic points ... so that if I ever have an inkling there might be water, I can drill a hole from the central keel section and let it all drain into my bilge.

Furthermore, I believe expanded polystyrene is more water resistant than PU foam ... but I would appreciate other thoughts here?

Thanks

Re: C19 - Major Structural Issues - Progress

Posted: Wed May 16, 2018 3:02 pm
by Fuzz
After going through what you have it is easy to understand why you want to do things different this time. Have you thought of running drain tubes to a central bilge? You could plug them in normal use and pull the plugs to check for water as needed.
It is good to see the progress you have made. I am sure things will be much better this time around.

Re: C19 - Major Structural Issues - Progress

Posted: Wed May 16, 2018 6:01 pm
by TomTom
Fuzz - yes I have thought of that - but I do want to fill then spaces with something as I am worried about the expansion and contraction of large volumes of air causing the sole to crack... PU foam would fill the cavities but prevent any water that got in from moving to the bottom and then being able to flow. Fitted Expanded Polystyrene would achieve this.

Short of the work of carving blocks of polystyrene to shape I cant see a downside unless there is something wrong with using expanded polystyrene.

And yes then each section could have a drain into the bilge.

Re: C19 - Major Structural Issues - Progress

Posted: Thu May 17, 2018 4:49 am
by icelikkilinc
I do not know if you have clearance but just as a thought.
Instead of PVC, you can make long boxes out of ply where you can route your wiring.
for example 3mt * 10cm * 10cm
no bonding issue like PVC
you can embed them to existing stringer structure and glass them to keep your structural integrity..
you can still pour and add foam under/around etc.. it you were to pour, even greater help on integrity.

Re: C19 - Major Structural Issues - Progress

Posted: Thu May 17, 2018 7:25 am
by TomTom
Thanks - so my plan is to run everything through the middle/ keel section. I will probably have two pvc pipes to seperate fuel and electric lines, but I will have an access hatch in the floor and no foam in the entire "keel section" ... and any water getting in would just drain into the bilge and be pumped out...

I want to put a limber hole between the outer stringers (outer from the keel, ie stringer nearest the hull sides) just in front of each frame.
If any water were to get in, it would drain downhill towards the keel. A simple hole drilled through the stringers closest to the keel - just in front of the frames could be drilled easily if I felt the need to inspect each section.

This is why I want to use Expanded Polystyrene block as it won't stick to the floor and stop water flowing down towards the keel.

I found this comment on BoatDesign.net ... wondered what the folks here thought about his comments?
Thanks for the response. It's true that polystyrene foam is cheap compared to expanded eurathane but it also has other properties that are superior. Polystyrene is truly closed cell, eurathane on the other hand is "closed" cell relative to it's density, the denser the higher it's resistance to absorbsion. Polystyrene does melt when exposed to gasoline and other petrochemicals and shouldn't be used where it will come in contact with those chemicals, but if utilized properly polystyrenes can make excellent flotation materials. I suggest that anyone who has an interest in using polystyrene as floatation material check out the U.S. Coastgard web site @ uscgboating.org/ and look at the "Boat Builders Handbook", and ASTMD-2842.
I know that there is conventional wisdom that condems the use of certain materials in boatbuilding but I believe they are the result of jumping to conclusions and myths. Like most things, sometimes it's just not so simple.

Re: C19 - Major Structural Issues - Progress

Posted: Thu May 17, 2018 6:52 pm
by Fuzz
Wish I knew the absolute correct answer when it comes to floatation foam. That is why I started the foam and where thread. Wanted to get the thoughts of lots of other builders.

Re: C19 - Major Structural Issues - Progress

Posted: Thu May 17, 2018 7:11 pm
by Jaysen
Build an accurate scale model?

Re: C19 - Major Structural Issues - Progress

Posted: Thu May 17, 2018 7:25 pm
by TomTom
Wish I knew the absolute correct answer when it comes to floatation foam.
Me too!

I want to hear what Jacques has to say on the subject of Expanded Polystyrene if used where no gasoline gets to it!

Re: C19 - Major Structural Issues - Progress

Posted: Thu May 17, 2018 10:49 pm
by fallguy1000
Things look great!

I have only opinion that you are going about things properly.

I doubt a bone dry bilge, too.

It would be far better to pull up a replaceable section of floor than to redo the entire sole, so a removable panel is also wise, in my book. I am still considering removable panels over my fuel tanks.

Extruded polystyrene is relatively cheap. Styrofoam WILL saturate-do NOT use it.

EDIT - Expanded polystyrene is styrofoam. Do not use. Extruded polystrene is closed cell and has lower water absorption rates. Expanded polystyrene WILL saturate. I posted this as I was dozing off!

I think extruded polystyrene is a great idea. You ought to do some calcs because the boat is wood; so you only need to offset engines and tanks and glass and epoxy and batteries, etc.

Good and thoughtful effort and planning. You will be rewarded.

Again, things look great.

Re: C19 - Major Structural Issues - Progress

Posted: Fri May 18, 2018 4:24 am
by TomTom
Thanks Fallguy - yes I want it done properly this time - but the truth is I tried pretty hard to achieve it last time too!!

At least I know I am using good resin this time; but a couple of scenarios posted on this forum and also taking to Boatyard’s and reading posts on other forums really does lead me to question the idea that you can truly seal Water out indefinitely.

Stories about of Boston Whalers with waterlogged foam and I have seen a fair few boats being gutted of the stuff in our local boat yard.

Some people swear by PU foam - others hate it.

In any event - other than the gasoline issue - what are the disadvantages of Expanded Polystyrene - is it more or less Water permeable than PU foam?

Re: C19 - Major Structural Issues - Progress

Posted: Fri May 18, 2018 6:00 am
by Capt UB
In a few Gheenoes I poured foam into heavy duty garden trash bags. I put the bag inside the compartment, pour foam inside bag. Most of the time I had room to tie the bag at the top. I could not do this under the sole of my FS14. Next build I may see if it will work.

Re: C19 - Major Structural Issues - Progress

Posted: Fri May 18, 2018 7:07 am
by TomTom
I thought about that too - good solution!

I read on an aluminum boat forum about doing this as there was the suggestion of corrosion issues between damp foam and the ally.

Re: C19 - Major Structural Issues - Progress

Posted: Fri May 18, 2018 9:17 am
by fallguy1000
I don't doubt your efforts either time Tom.

My build is not without issues. Believe me..

You cannot use expanded polystyrene. That is styrofoam. It is open celled and will overtime saturate and become heavy. It does not ever dry once saturated. How do I know? Hot tub covers are made from 3-5" thick foam. Ours became waterlogged and I tried to dry them for about a month in an overheated room with fans. The weight dropped a couple of pounds, but they were too heavy to ever use again as tub covers and were replaced at a cost of about $500. The water gets in and piles up inside the cellular structure voids and it can never leave. Maybe vacuum might have worked?

You can use extruded polystyrene.

Get the tds of the product you want to use. It should have a water absorption rate similar to buoyancy foams.

If you are concerned about fuel in the bilge; you could epoxy coat the foam. I would probably not.

I would probably tab the foam up off the bilge bottom a bit for drainage and to avoid a chemical breakdown. You could tape it and then tab it with epoxy and glass or put epoxied blocks of foam under larger panels.

Extruded polystyrene is used as an insulating material in homes against concrete walls. The vapor barriers are placed directly on concrete; then the extruded is inserted and then the walls. Any damage to the vapor barrier on install will allow ingress to the extruded poly, but it doesn't matter as the absoprtion rate is 1% or less.

Do NOT use expanded polystyrene. Extruded only.

Re: C19 - Major Structural Issues - Progress

Posted: Fri May 18, 2018 9:31 am
by fallguy1000
http://www.owenscorning.com/NetworkShar ... lletin.pdf

This has absorption rates for the OC products and compares xps to eps. X-extruded vs E-expanded. Expanded will gain water overtime and saturate.

The percentages are misleading in the tds.

If you gain 5% water in a cubic foot of foam; the water will weigh more than the foam and it will mever dry out and your boat will become heavy and moisture laden always.

Re: C19 - Major Structural Issues - Progress

Posted: Fri May 18, 2018 9:41 am
by fallguy1000
One more link for doubters.

Expanded polystyrene was removed from a home foundation barrier in Mn. The saturation rate of expanded foam was 18.9%.

A cubic foot of foam weighs about ?5 pounds or less. 18% of a cubic foot of water is 11 pounds.

They also removed extruded polystyrene. You can see, it, too had absorbed some water over the 15 or so year project.

https://www.achfoam.com/ACH/media/ACH/d ... -Facts.pdf

Re: C19 - Major Structural Issues - Progress

Posted: Fri May 18, 2018 9:45 am
by fallguy1000
It would be good if we had someone post the tds of the marine buoyancy foam Jeff sells with the absorprtion rate. I am outta time now.

Re: C19 - Major Structural Issues - Progress

Posted: Tue Oct 09, 2018 10:14 am
by lawtoolguy
Hey TomTom,

I received your message and jumped on to see what I was missing. Looks like you have got a good start to fixing your C19 or say C21. Before I started my rebuild I spent weeks reading great info from here before deciding to build my integral bracket. Knowing that it was my build I didn't expect any real design help. If I had it to do again I would use the method Daytrip used and work from a female mold. The original hull was a 23 ft with a walk around cabin which helped to balance out the hull and carry the twin four strokes sitting back 27 inches. The boat handles great for us now but I don't have anything to compare it too as we bought it with a blown V8 and other issue's. It averages a top speed of around 33 knots + or - depending on load. I also added a 30 gallon fresh tank under the passenger side seat which adds some more weight. Here are the speed results from before the water tank add. This is with a stock Yamaha OEM 13 1/4 x 17 RH aluminum prop matching on each motor which could probably be improved but it works for us.

1000 RPM = 4 Knots
2000 RPM = 7 Knots
3000 RPM = 9 Knots
4000 RPM = 20 Knots
5000 RPM = 28 Knots
5900 RPM = 33 Knots

The bracket was allot of work but in the end I am glad I did it. We use the dive platform allot and our five dogs now climb the ladder on there own and use the dive platform to get back on the boat. Good luck with your decision on your build and thanks for sharing...Tim

Re: C19 - Major Structural Issues - Progress

Posted: Sun Oct 14, 2018 8:47 pm
by cracked_ribs
fallguy1000 wrote: Fri May 18, 2018 9:41 am One more link for doubters.

Expanded polystyrene was removed from a home foundation barrier in Mn. The saturation rate of expanded foam was 18.9%.

A cubic foot of foam weighs about ?5 pounds or less. 18% of a cubic foot of water is 11 pounds.

They also removed extruded polystyrene. You can see, it, too had absorbed some water over the 15 or so year project.

https://www.achfoam.com/ACH/media/ACH/d ... -Facts.pdf
I'm not sure if they're defining their terms differently but in the above-referenced link they're saying that the extruded polystyrene ended up with 18.9% moisture content.

I don't see any mention of expanded polystyrene.

Are they confused about the nomenclature?

Re: C19 - Major Structural Issues - Progress

Posted: Sun Oct 14, 2018 9:51 pm
by fallguy1000
I can only tell you what I know.

The city of St Paul will NOT allow you to insulate anything with expanded polystyrene, anything can be insulated with extruded.

So, the link is certainly confusing.

However, I can say with 100% certainty that styrofoam takes on water overtime. And the water will NOT leave.

I only trust extruded and according to the link, even that is a bad idea.

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 02, 2018 7:42 am
by TomTom
Ok I know you all like pictures so I am posting my boat re-build progress here. I have been away a lot this year - so slow progress - but we are getting there now.

Almost all the frames and stringers under the sole are taped back in and now working on the side frames and gluing the cleats in. These I made out of 2x2 cypress which I split diagonally - so I have triangular cleats which give me lots of gluing surface area.

I will probably just go back to the tried and true expanded foam method between compartments - it is hard for one to imagine that water would get through all those taped seams and under the sole with that much gluing area - but stranger things have happened! My oscillating saw gives me a false sense of confidence in my ability to cut open and inspect things should I get worried and want to have a look.

Remember - I am binning the idea of all chase tubes and running everything down the central keel area which I will have access to and which will have a bilge in it.

Image

Image

I have also decided to extend the hull; I know that I went back and forth on this for ages - but I feel like after all this work, I might as well do it, spend a bit more time and get it how I want. So it is going to get 2 feet added on at the transom...of that I am committed now...

I am still vacillating (and I know Jacques will not chime in on this one :wink: :wink: ) about building my own outboard bracket extension like Daytrip did - with the stringers extended through the hull.

What I was thinking was that because I have to have a frame 8 inches in front of the transom, I could make my outboard bracket stick out 16-18 inches and have the engine partially tilt up into the 8 inch space between the transom and the frame...

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 02, 2018 10:48 am
by glossieblack
I can understand why, after the trials and tribulations you've been through, why you want to end up with something a little longer, and with bracket. 8) Just do it. :D

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 02, 2018 1:33 pm
by TomTom
So this is what I was thinking. The bracket would set back about 16 inches. Jacques says there must be a bulkhead a minimum of 8 inches in front of the transom for structure, so in total I would have about a 24 inch "motor well"...

All comments on upsides, downsides, risks are welcome!

Image
Image
Image
Image

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 02, 2018 1:44 pm
by cracked_ribs
Upsides:

1) the usual bracket stuff like cleaner water for the prop
2) your design looks awesome
3) you will cement your place in bateau building history

Downsides:

1) if Jacques won't approve the changes you won't have his input on the lamination schedule
2) it might have a slightly more pronounced hump getting on plane - I recall you saying something about the pangas being maybe a more practical design for your style of fishing and although I don't want to discourage you because I think your idea looks awesome, that's the one concern I would have. Bracket boats tend to squat a bit on acceleration so I'm not sure how the transition to plane would look.

But I am really hoping it gets the thumbs up from the boss because yeah, that looks awesome.

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 02, 2018 1:53 pm
by TomTom
2) it might have a slightly more pronounced hump getting on plane - I recall you saying something about the pangas being maybe a more practical design for your style of fishing and although I don't want to discourage you because I think your idea looks awesome, that's the one concern I would have. Bracket boats tend to squat a bit on acceleration so I'm not sure how the transition to plane would look.
Thanks for the comments ... I was actually wishfully thinking that this might give me a slightly higher hull speed (longer waterline length) and possibly improve displacement speed efficiency ... but I suspect any advantage very negligible if at all?

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 02, 2018 3:34 pm
by terrulian
The formula is 1.34 x sqrt LWL so you can do the comparison; I don't know the waterline length but roughly you may gain about .1 knot at displacement speed. Tom would have a more accurate figure.

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 02, 2018 3:44 pm
by cracked_ribs
If I had to guess (and I do because I have no real information so it's guessing or nothing) I would think that the two effects might roughly cancel each other out?

Intuitively I'm picturing a higher pure hull speed - like say a 10hp kicker would drive it at 6 knots instead of 5 - but more noticeable squat at 10. But I am super unqualified to make anything but a guess. For all I know the turbulent water under the bracket would actually aerate more efficiently, like a micro hull step, and it would actually plane sooner.

Bottom line: if this works, everyone is going to want one. I personally can't explain why a lengthened C19 with a bracket speaks to me more than a C21, but it just does. It seems like it would be a real missile.

Re: C19 - Major Structural Issues - Progress

Posted: Sun Dec 02, 2018 7:07 pm
by Fuzz
I built a bracket similar to what Daytrip did for my Sintas 21. Even with the extra floatation from the bracket the stern did sit a little lower at rest. I would have to measure but I think it is close to 24 inches of set back. You really need to do weight and balance calculations if you do this. My hull has a little designed in rocker. Between the rocker and all the weight on her tail she wants to porpoise. At first I had the motor mounted way too low and she would try to toss you plumb out. After I got the motor raised enough things were much better. Now with no tabs it just starts to porpoise around 40mph. By carrying the stringers through the transom and out into the bracket I have no worries about it being strong enough.

Re: C19 - Major Structural Issues - Progress

Posted: Mon Dec 03, 2018 1:56 am
by TomTom
Fuzz thanks - do you guys think that porpoising is a natural problem with an outboard style bracket set up - or is it more of a weight and balance thing.

I am doing my repairs right by the ocean and was thinking I could mount the engine and then stick the console in loose and move batteries, fuel etc around to work out where she sits nicely. I kinda have a clean slate from a weight and balance point of view; but I guess what I am trying to work out is how much is porpoising an inherent risk with outboard brackets and how much of it comes down to the weight and balance thing.

The bracket will definitely be more work to do, so really just trying to work out if I am just borrowing trouble on this one. For me the extension is a no brainer, but I keep doing u turns with the "bracket" idea.

Re: C19 - Major Structural Issues - Progress

Posted: Mon Dec 03, 2018 3:10 am
by BarraMan
I've got nothing for you on this. I have never had anything to do with brackets.

The motor on my boat sits on a jack plate with an 8" set back and an inbuilt 2" lift with a further 6" available from the jack plate.

My boat doesn't porpoise - ever!

Trimming the motor out lifts the bow and eventually results in cavitation. Lifting the jack plate too high also results in cavitation.

Re: C19 - Major Structural Issues - Progress

Posted: Mon Dec 03, 2018 5:09 am
by fallguy1000
If you have porpoising worries, can't you alleviate these some by building the bracket at 14 degrees to water?

Re: C19 - Major Structural Issues - Progress

Posted: Mon Dec 03, 2018 7:30 am
by TomTom
If you have porpoising worries, can't you alleviate these some by building the bracket at 14 degrees to water?
yes ... I think most transom brackets are built with more angle so that you have more wriggle room with your outboard settings.

I guess what I am trying to figure out is whether on a boat like this, there would really be any major advantages (other than an extra 16 inches in cockpit length) to a bracket - or whether I am just borrowing trouble!

Re: C19 - Major Structural Issues - Progress

Posted: Mon Dec 03, 2018 2:53 pm
by Fuzz
Like I said my hull has some designed in rocker. I am sure that has a lot to do with it.
You being able to put the boat in the water to check the balance would be a huge help. Having the motor on a bracket makes the boat feel a lot larger for sure.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Wed Dec 05, 2018 12:49 pm
by TomTom
I am about neck and neck with Eric now on his C21 - I thought he was going to buy a bolt on bracket...

I am still thinking about it and then the other monkey on my shoulder reminds me of the KISS principle! The stretch is definitely happening though!!

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Wed Dec 05, 2018 2:14 pm
by Fuzz
I have now built one bracket and also installed one on a different boat that was a bolt on.
The bolt on was fast and easy. It was also spendy. All said and done I had $5000 in the bracket.
If I were to do another home built bracket it would be done just like the one I and Daytrip did. I would not trust a home built one that bolts on but I feel different about one built by running the stringers out through the transom. To me the key is the stringers carrying the weight and all the rest just being a bonus.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sun Dec 09, 2018 10:50 pm
by OneWayTraffic
I would add a gusset to the motor mount if it extends more than a little above the bracket surface.

If you use the same, or greater scantlings as the transom itself, and extend out the stringers, along with a generous fillet and a couple of layers tape between the bracket and transom, I can't see it failing. I am no engineer however.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Fri Dec 14, 2018 7:10 am
by Christer
The OcraCoke boats have versions with built-in brackets based on through-transom stringers, and it looks good and seems to work well. It's a Carolina Sportfish style boat like the Bateau CS23/25, but I'd reckon the principle would be the same.

Like this: https://bandbyachtdesigns.com/ocracoke-256-2/

Can't wait to see how this turns out! Best of luck!

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Tue Dec 18, 2018 6:40 am
by TomTom
Thanks Christer - yes I had secretly been looking at the B and B boats - though I am not sure if one is allowed to mention that here!

I am not particularly worried about making it strong enough if I extend the stringers through the transom to make the bracket. I think it is very doable.

This bearing in mind I am the guy that drove around unknowingly in a boat that basically had half the stringers not even properly taped to the hull, and half the inner sheathing bonded with a chewing-gum-like sorry-ass excuse for resin for most of the boat's life. I can see how faith in the amateur builder could be lacking sometimes!! But it did serve as a remarkable testament to the design that it still didn't fall apart! I am confident that the hull will be stronger than at any point in its history this time around!!

So I personally think there is probably plenty of strength and redundancy - though I can understand why the designer wouldn't want to stick his neck out on this one!

I guess though, I am still slightly confused how a 10% hull extension plus a commercial bolt on bracket would be given the designers ok, but that a 10% hull extension and then an 18 inch through transom "bracket" made with a stringer extension wouldn't be? I mean I suppose one could say this is closer to say a 15% hull extension - but I don't really understand how the stresses would be different to a 10% hull extension and a bolt on commercial bracket? Anyone following me here?! You are still essentially adding the same amount of length. Maybe I just don't understand how the stresses would be transferred.

What concerns me more is whether I am just borrowing trouble in terms of the boat's performance - will I suddenly end up with a boat that rides totally different, porpoises, is out of balance and has a massive rooster tail! Not that rooster tails don't look cool - but I digress...

I guess I am more worried about my ability to get all the angles correct and end up with something that gains me not only an extra 18" of hull space (in addition to the 10% hull extension) ... but that also doesn't screw up a perfectly good boat!

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Tue Dec 18, 2018 8:34 am
by OrangeQuest
TomTom wrote: Tue Dec 18, 2018 6:40 am
I guess though, I am still slightly confused how a 10% hull extension plus a commercial bolt on bracket would be given the designers ok, but that a 10% hull extension and then an 18 inch through transom "bracket" made with a stringer extension wouldn't be? I mean I suppose one could say this is closer to say a 15% hull extension - but I don't really understand how the stresses would be different to a 10% hull extension and a bolt on commercial bracket? Anyone following me here?! You are still essentially adding the same amount of length. Maybe I just don't understand how the stresses would be transferred.
When you extend the back of the boat with just your stringers you are losing all the strength of the whole back of the boat and putting it just on the stringers. The transom is strong not only because of the thickness of the transom but because the stringers' knees, the hull bottom, the hull sides and the hull deck/gunnels. The transom is beefed up by all of the boat as a whole. You lose that "whole" when you go with just the stringers. A bracket bolted to the transom still uses the whole hull for support. An outboard pulls at the top of the transom and pushes at the bottom and is always applying that twisting force to the transom. The transom is strong enough as a whole to take the extra twisting force. Take away everything but the stringers and you lose the extra support.

THAT IS MY THEORY! But I am in no way an engineer but sometimes I play one on TV. :)

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Tue Dec 18, 2018 10:50 am
by fallguy1000
TomTom wrote: Tue Dec 18, 2018 6:40 am Thanks Christer - yes I had secretly been looking at the B and B boats - though I am not sure if one is allowed to mention that here!

I am not particularly worried about making it strong enough if I extend the stringers through the transom to make the bracket. I think it is very doable.

This bearing in mind I am the guy that drove around unknowingly in a boat that basically had half the stringers not even properly taped to the hull, and half the inner sheathing bonded with a chewing-gum-like sorry-ass excuse for resin for most of the boat's life. I can see how faith in the amateur builder could be lacking sometimes!! But it did serve as a remarkable testament to the design that it still didn't fall apart! I am confident that the hull will be stronger than at any point in its history this time around!!

So I personally think there is probably plenty of strength and redundancy - though I can understand why the designer wouldn't want to stick his neck out on this one!

I guess though, I am still slightly confused how a 10% hull extension plus a commercial bolt on bracket would be given the designers ok, but that a 10% hull extension and then an 18 inch through transom "bracket" made with a stringer extension wouldn't be? I mean I suppose one could say this is closer to say a 15% hull extension - but I don't really understand how the stresses would be different to a 10% hull extension and a bolt on commercial bracket? Anyone following me here?! You are still essentially adding the same amount of length. Maybe I just don't understand how the stresses would be transferred.

What concerns me more is whether I am just borrowing trouble in terms of the boat's performance - will I suddenly end up with a boat that rides totally different, porpoises, is out of balance and has a massive rooster tail! Not that rooster tails don't look cool - but I digress...

I guess I am more worried about my ability to get all the angles correct and end up with something that gains me not only an extra 18" of hull space (in addition to the 10% hull extension) ... but that also doesn't screw up a perfectly good boat!
I enjoyed the self depricating remarks TomTom.

I would caution you against inherent bias. That is you saying if I do the work right this time; it will be strong enough.

I think the twisting forces on a stringer bracket would be powerful.

Consider for a moment the absurd.

You build a stringer out of one foot chunks. Then the extension is 18", so the last foot isn't connected, just glass wrapped. So you hit some rogue waves and lose the engine.... a ridiculous scenario, but something like a knot in a stringer weakens it.

I wish I could help because I don't think the idea is meritless; but must be done well and proper.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Tue Dec 18, 2018 1:52 pm
by cracked_ribs
Let's also consider, though, that there have been stringer extension brackets built on this forum which hold up...at least one of which had what, twin 300s on a 28' hull? 30" of setback?

I mean nothing you do is going to subject a C19 bracket to the kind of forces that Bertram endures.

Sure it's a cantilevered beam but it's pretty short and boxed up like crazy. It really doesn't jump out at me as unmanageable.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Tue Dec 18, 2018 4:23 pm
by Fuzz
I built a bracket by extending stringers through the transom. With the bracket box and deck glassed into the transom I can see no reason there is a weakness. As a matter of fact I have more faith in a bracket built this way than a factory built bolt on one. But this is just my opinion :wink:

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Wed Dec 19, 2018 4:45 am
by TomTom
Thank you all for your support, good humour and wise words.

I shall continue to ponder the structural issue as I finish gluing the last cleats in place; I will continue to test the integrity of my workmanship with the ancient, well trusted and highly sophisticated technique of kicking everything repeatedly to ensure soundness.

I am then going to flip the hull and remove the transom in a flurry of makita induced madness!

The there will be less room for debate! In the words of a French proverb ... “The first step binds one to the second”!!

Structural issues aside - can anyone see any glaringly obvious problems I could create with the boats performance - or is a bracket a fairly safe bet with regards to knowing the outcome of how the boat will behave?

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Wed Dec 19, 2018 9:32 pm
by cracked_ribs
The possible performance issues should be relatively predictable: depending on the specifics of the bracket it may tend to sit lower in the stern, squat more before reaching plane, or porpoise at high speeds. IIRC you have a 150 on there which seems like the upper limit for power on something this light and with this little deadrise, so I would take the possibility of porpoising at WOT seriously.

On the other hand, you may avoid all of the above by lengthening the hull at the same time and I wouldn't expect any of the possible issues to present at extreme levels. Chances are if you don't go crazy on bracket length or make one with really inadequate displacement, you'll have some slight quirks that you notice because you've run it a bunch already, along with some performance gains by putting the prop in clean, shallow water.

Just thinking this over the other night it struck me that if you started a 1m wide bracket say , 50mm up from the keel and slanted upwards another 50mm to the edges and the whole V tapered upwards the same amount towards the stern...you're not really getting into significant displacement until you have 100mm/4" of hull in the water. If the C19 waterline is around 200mm at the transom, you're probably getting something like 100kgs of floatation out of a bracket so if you imagine a big guy standing on a swim platform, well, that's probably about the trim you'll get at rest. Of course, that would be a guy hanging there with no motor, so the static trim might not be affected much at all.

Again totally ballparking this but figure an area of 1 m^2 * 10cm deep = 100l of water displaced...I guess there are frustum shapes or something where you could calculate the displacement of the upward sloping V section but I can't visualize it easily. I suppose you could get pretty close by using one quarter the area * height of the V section, but I never post unless I'm drinking so at the moment I'd just guess that the V will offset the materials in theb bracket and not much more. No doubt you have or will have exact dimensions before you start sawing so this could obviously all be calculated as I'm sure you know and can do.

I just thought I would mention the 100kg figure because it struck me that the outer stringers are about a half meter off the centreline so it's very easy to approximate the displacement in metric. Not that you necessarily want a 1m long bracket but just for simple illustrative purposes, there's some rough numbers.

I am thinking hard about a similar boat myself; it's interesting because "podding" boats in this size range and even smaller is extremely popular around here and I like the narrow beam with the extra interior space and performance effects of relocating the motor. But then at the same time my understanding is that Jacques has designed a boat or two at this point in his career, and he doesn't seem enthused about this configuration. So maybe the light weight of the construction method or the relatively flat deadrise makes it more sensitive to the effects of the bracket? I'm not sure. It's sort of the minimum length I usually see anyone recommending brackets on...but then locally as I say we see tons of 80s glass boats 17-20' podded with aluminum brackets and guys rave about them.

Anyway I'm looking forward to the rebuild, whatever you do. I think at this point the only opinion really worth soliciting is Jacques'.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sun Dec 23, 2018 1:43 am
by TomTom
Image
Image

Some progress pictures whilst I ponder whether to "bracket or not to bracket"...

I have found that cheap 3mm ply is a great way to cut templates and do all your fitting before making mistakes on expensive marine ply... here I am fitting floor panels...

I have decided to seal each compartment individually as a way of doing my "quality" control... my theory is that it will be easier to get a good bond on each individual small piece of plywood and I will also be able to check the bond before moving onto the next compartment...

I believe water has a remarkable way to travel by "capillary action" and I am not convinced of my ability to glue the floor down in big sheets and still be 100% sure that I havent left small "passages" for water to travel through.... I think this seems like a safer way to avoid this.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sun Dec 23, 2018 6:06 am
by OrangeQuest
I use cheap reclaimed plywood from a furniture warehouse near my warehouse. They put it by their dumpster and I just grab what they have with a trailer. A lot of it is used to protect table tops when shipping so they are not 4X8 sheets of plywood and they fall apart near water but are great for making templates. And it is free wood.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sun Dec 23, 2018 5:19 pm
by fallguy1000
Templating is smart. Smarter when sourcing is hard.

I template with cardboard. With foam; there are rebates and tons of planning required.

It is looking good, but if you were gonna extend stringers; hasn't that ship sailed or am i seeing things wrong?

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sun Dec 23, 2018 5:20 pm
by fallguy1000
Yup, that is the bow on that high freeboard beast!

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sun Dec 23, 2018 5:22 pm
by fallguy1000
The only thing to watch for will be utilization or yield out of the sheet. Cutting lots of pieces can hurt yields. If you plan well; the opposite.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sat Jan 12, 2019 11:36 am
by TomTom
Everyone likes pictures right!

Mocked up a 2 foot transom extension for my C19 ...


Image

Image

Obviously it should look better once done and I do need to trim the transom mock and make it narrower so the extension follows the curve of the hull.... but this is enough to get an idea!

Thoughts?

Am toying with a forward slope from the transom like this...

Image

Obviously my boat wont end up being a 32 foot Regulator... but wondered what everyone thought

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sat Jan 12, 2019 11:48 am
by Bogieman
Nice!

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sat Jan 12, 2019 2:46 pm
by Fuzz
If you do it that way you lose some of the benefits of a bracket like being able to run the motor higher. But you gain more boat all the way around. And for my money I think there is less chance of having problems or strange behaviours.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sat Jan 12, 2019 3:21 pm
by TomTom
Fuzz I am led to believe a bracket with such a shallow dead rise doesn’t confer that many advantages and if it does u only see them at high speeds. I don’t go anywhere over 24 kts so my main interest is hassle free increase in deck space and if possible better hull speeds

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sun Jan 13, 2019 12:22 pm
by fallguy1000
The forward rake sort of defeats the purpose.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sun Jan 13, 2019 1:09 pm
by Jaysen
Isn’t that really just enclosed bracket? The transom seem to be in front of the motor and span the entire width. The 45s look to be tying the tip of a bracket/clamping board to the the actual transom. The actual mounting for the motor appears to have the traditional angle of a transom. I’m thinking it’s the cut in the side, not the actual face of the motor mount/transom that is being refer to as “angled forward”.

Am I missing something?

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sun Jan 13, 2019 2:59 pm
by TomTom
i only just noticed the step and inbuilt bracket. I was looking at the styling/ sheer line.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sun Jan 13, 2019 11:40 pm
by cracked_ribs
My only concern with the transom sheer on that regulator is that on a smaller boat you won't have the resistance to boarding waves that a reverse-raked transom would give you. With the reverse rake, the buoyancy increases at a faster rate the more of the transom is immersed and the shape will tend to force the stern up and over waves and when backing down.

If you go to a "euro transom" as we call those here, you'll be a little bit more vulnerable to following seas. Granted you'll still have the full bulkhead keeping the cockpit dry but you're more likely to see the splash well doing some work IMO.

OTOH I hardly see a glass boat made these days that is not in that style so I'm sure that the difference would be minor in all but the worst conditions. Locally, when entering the big river and dodging tug and freighter traffic, I have been overtaken by pretty nasty waves and that may have made me paranoid about transom design.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sun Jan 13, 2019 11:54 pm
by TomTom
Thanks Cracked-ribs - I had never really thought of that.... but makes sense ... though you still get reserve bounyancy up to the top of the transom. At which point water would start coming into the motor well in whatever case.

I think I am going to do a motor well that slants down towards the transom to create a space under it that can be accessed from inside the cockpit ... something like this ...

Image

It is really nice to have somewhere to kick all your loose rigging buckets, chopping board, lures etc whilst fighting a fish. It also means your motor well is well above the waterline and drains easily out.
The forward rake sort of defeats the purpose
You’ve lost me a bit Fallguy?

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Mon Jan 14, 2019 12:47 am
by cracked_ribs
That splashwell looks quite a bit like one on one of the boats I grew up with. It worked really well, both for dealing with following waves and for giving us foot room to work at the transom, exactly as you say.

Really looking forward to seeing this reno job.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Mon Jan 14, 2019 9:04 am
by pee wee
TomTom wrote: Sun Jan 13, 2019 11:54 pm
I think I am going to do a motor well that slants down towards the transom to create a space under it that can be accessed from inside the cockpit ... something like this ...

Image

It is really nice to have somewhere to kick all your loose rigging buckets, chopping board, lures etc whilst fighting a fish. It also means your motor well is well above the waterline and drains easily out.
That motor well bulkhead is structural in many of these designs, I don't know if it would be needed in your case. It would be a convenient place to shove things out of the way, though.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Mon Jan 14, 2019 1:10 pm
by TomTom
That motor well bulkhead is structural in many of these designs, I don't know if it would be needed in your case. It would be a convenient place to shove things out of the way, though.
Yes - I am figuring that the additional rear slanting piece will compensate for the removal of the middle of the motor well bulkhead. I will leave it as a frame however.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sun Jan 20, 2019 8:12 am
by TomTom
Image

Well there is no going back now!!

The extension will be done from the transom end - and as you can see I have cut the hull so that I can add a lower side panel first that follows the hull contours and takes its shape from the topside panel. The stringers will be extended and the existing transom returned but trimmed down to fit the slightly narrower stern created by the slight curve as the hull panels extend back. The hull bottom will then be then cut to fit into this - ensuring I keep everything straight and avoid any hook or rocker, I feel like it should turn out OK!!

I am planning to add between one and two frames (depending on what final length I decide on). I am also going to add a skeg - as the boat is quite hard to steer at slow speeds and in wind. I will butt join the panel overlaps and have a frame right above this butt joint. I will also extend the lifting strakes across the joint which should add lots of strength there.

I will keep the lamination schedule the same as originally designed.

All the gaps between stringers and frames will be foam filled for added stiffness. Sole of boat will get a layer of biaxial.

I am toying with adding 3 feet...but I know that is more than 10%!! But if I did this I would add two extra frames and I am not increasing the frame spacing.. I am also going to try really hard to keep the boat lighter than before...

Image

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sun Jan 20, 2019 8:26 am
by Jaysen
Tom, the proxy.php from boatdesign.net is not allowing you to embed via their site. You'll need to use direct links to the image. We can see the images if you use URL so we can click on it. Like this.

Image 1

Image 2

When posting that looks like

Code: Select all

[url=https://www.boatdesign.net/proxy.php?image=https%3A%2F%2F7600230-646359173733290791.preview.editmysite.com%2Fuploads%2F7%2F6%2F0%2F0%2F7600230%2Fimg-6191_orig.jpg&hash=7b303f47cfc2a3cd6068bb3b0cda20b6]Image 1[/url]

[url=https://www.boatdesign.net/proxy.php?image=https%3A%2F%2F7600230-646359173733290791.preview.editmysite.com%2Fuploads%2F7%2F6%2F0%2F0%2F7600230%2F82f216cc-c3a0-4a4a-aec2-a36a2f476cf5_orig.jpg&hash=765e130b1511a7a113b642943ba12fd1]Image 2[/url]
Problem is that your site doesn't like being linked to so you have to hit refresh. They are trying to prevent folks from using their images in other places. It's a common tactic sites use.

To embed you need to use the link (from your url it is the decoding of https%3A%2F%2F7600230-646359173733290791.preview.editmysite.com%2Fuploads%2F7%2F6%2F0%2F0%2F7600230%2F82f216cc-c3a0-4a4a-aec2-a36a2f476cf5_orig.jpg&hash=765e130b1511a7a113b642943ba12fd1 which is https://7600230-646359173733290791.prev ... 943ba12fd1) but it doesn't resolve properly.

Hope that all made sense.

Alternatively you can just upload to the bateau gallery and link from there. It all works nicely together.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sun Jan 20, 2019 8:56 am
by TomTom
Thanks Jaysen - I was being lazy - will do it how I normally do!

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Mon Jan 21, 2019 12:17 pm
by TomTom
Image

Have cut back the strakes and sanded down to wood and then biaxial and slowly tapering it where the bottom panels will meet.

Wood was 8% moisture content and in good shape.

Image

You can see here where I split the stringers and will extend them from the bulkhead frame and include them under the tape that does the frame corners.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Mon Jan 21, 2019 8:45 pm
by fallguy1000
Looking good afaik. Big job for sure.

Can you rebate the plywood for tapes? I suppose a bit of fairing won't be horrible.

I have lots to fair, so looking at all fairing.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Wed Jan 23, 2019 1:03 pm
by TomTom
I suppose a bit of fairing won't be horrible.
All fairing is horrible!! But I think you have a more Herculean amount ahead of you than I do - I will bear that in mind as I grumble my way along!

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Mon Apr 29, 2019 5:01 pm
by TomTom
I feel like today was enough of a milestone to warrant a picture... so I glassed my extension on my C19 today... no going back now... I feel like we have rounded the bottom of the curve on this rebuild!


I have to say that I am quite happy with the progress. I also can really recommend the technique of mixing cabosil (which I read about elsewhere on this forum) with the first layer of epoxy when laying down biaxial. It has made such a difference to getting rid of the air bubbles that plagued me to begin with and I think were often the result of imperfections/ dents in the wood - or gaps between the biaxial fibers.

I am also a Peel-ply fan!! Although today we filled the weave with thickened epoxy as it is the final layer and the fairing starts tomorrow, so I thought I would get a head start with some shaping and filling.

Because I extended the hull by extending the stringers first, I ended up glassing the inside of the hull bottom panels whilst flat and before stitching them together. This has allowed me to fillet then stringers in place from the underside of the upturned hull. I will tape the stringers to the transom (taping a vertical surface upside down isn't too hard) and I think this will be plenty strong enough to flip the hull once I finish fairing and painting the bottom.

Here are two pics... I wish to add that Jacques ... as usual ... was right and I probably could have built a whole new hull in less time. But ... I have learnt a lot ... and I think its nice in our throw away society to sometimes repair things rather than just replace them. Call me sentimental!!

A long way to go... but today was satisfying.

I have turned the pics upside down to help you see the lines better...

Image

Image

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Mon Apr 29, 2019 5:41 pm
by piperdown
Very nice :D

It is nice seeing someone else that has a "fix it" attitude versus throwing items away (except for cell phones!).

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Tue Apr 30, 2019 12:15 am
by Fuzz
Good on you for doing this. I hope this will turn out to be an even better boat for you.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Tue Apr 30, 2019 7:50 am
by Jeff
Really nice work!!! Jeff

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Wed May 01, 2019 5:28 pm
by TomTom
Urghhh ... I may have jumped the gun with y showing off...

I thought I had everything absolutely level ... but it looks like I have a little rocker that seems to get worse towards the chines.

The keel is level with no rocker. Not sure how this happened because I used the same transom shape as the original one that existed ... and the boat is a constant deadrise hull. I triple checked I had all my stringers level with a hose pipe and all the corners are level, the keel is level and the stringers are level .. so I am a little confused how this happened.

In any case, this is what it looks like when I put a straight edge along it. There appears to be a slight bulge where I joined the bottom panels and this might be causing some of this. I can rock the straight edge over this "hump" which is fairly uniformly focus at the butt joint. I don't want to grind it down for fear of weakening the joint.

Image
Image
Image

I am not sure whether to leave it ... don't really know how this will affect the boats performance - or I was thinking of building the areas towards the chines up ... it would effectively make the hull a variable deadrise hull as this would flatten the transom angle .... but it would take the rocker out!!

Wondering which would be the better option for a planing hull that will spend much of its life trolling at 8 kts!!

Any input from those more talented and knowledgeable would be very much aporeciated!

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Wed May 01, 2019 6:31 pm
by Capt UB
Don't forget, you will be fairing/shaping the hull. Few coats of graphite/epoxy....

Also, are you installing a skeg?

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Wed May 01, 2019 6:40 pm
by Capt UB
This is from my plans for the LM18. Doesn't look bad, 1/4" maybe but not more!?

Since this is a planing boat, it is important to have a straight running surface. The rear part
of the bottom must be straight from the mid seat to the transom. Straight means that a
straight edge dropped lengthwise on the bottom should not show a gap of more than
¼", either convex or concave. A convex bottom in profile is said to have rocker, a
convex one is hogged or has hook.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Wed May 01, 2019 6:55 pm
by Browndog
In many of Jacques responses I’ve noticed that he has indicated that the small amount of hook that you are showing is intentional to aid in the proper achievement of trim. Perhaps I’ve misunderstood, but I don’t believe that you have a problem.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Wed May 01, 2019 7:06 pm
by TomTom
Thats interesting - do you have any examples of posts where he Jacques mentioned that?

I may be being too pedantic!!

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Wed May 01, 2019 7:31 pm
by Capt UB

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Wed May 01, 2019 9:30 pm
by TomW1
Tom don't worry about it, it will help when you are on plane and will not affect trolling. If you want fill it in when you are fairing but there is really not a need to. It is caused by the multiple layers of fiberglass tape on the transom, so maybe flair it forward a foot or two.

Tom

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Thu May 02, 2019 1:13 am
by TomTom
Thanks Tom - would be great if I could just leave it - but I don't really understand how it will help when I am on the plane?

I thought this sort of thing made it more likely for the boat to have a bow high attitude or more of a hump?

Its sort of doing the opposite of a chine flat isn't it?

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Thu May 02, 2019 4:19 am
by TomW1
TomTom wrote: Thu May 02, 2019 1:13 am Thanks Tom - would be great if I could just leave it - but I don't really understand how it will help when I am on the plane?

I thought this sort of thing made it more likely for the boat to have a bow high attitude or more of a hump?

Its sort of doing the opposite of a chine flat isn't it?
i

Tom think about it, if you have a dip like yours before the transom it is going to push the transom up and the bow down. Jacques purposely designs it in some boats. Just fair it out as much as you want if your not comfortable with it.

Tom

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Thu May 02, 2019 7:43 am
by TomTom
Tom - for once you have lost me... I would agree if the issue was the other way around ... ie the transom was slightly above (with boat upside down) the line of the straight edge ... so in effect you have something a bit like a trim tab or a flap on an aircraft at the back.

Mine drops the other way.

I have lined my straight edge up between where the strakes will be and its really only bad on the last section between the outer strake and the chine ... and is partly caused by a bulge at the hull bottom panel extension, making the straight edge rock over this and probably making it look worse than it is.

Image

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Thu May 02, 2019 10:27 am
by Dougster
I see it like TomTom. It's not something I'm real familiar with, but the pic looks to me like the hull has a tiny bit of hog, not hook.

Dougster

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Fri May 03, 2019 8:22 am
by topwater
Looks like a little bit of rocker to me .

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Fri May 03, 2019 8:46 am
by BB Sig
topwater wrote: Fri May 03, 2019 8:22 am Looks like a little bit of rocker to me .
It looks like rocker to me as well. Keep in mind the boat is upside down right now...

Barry's basic explanations:

Hook would be where the transom is touching the straight edge and the gap was between the transom and the original hull.

Rocker is where the transom does not touch the straight edge and the gap is larger at the transom than anywhere else.

I would venture to say you will be fine unless you are trying to win races! :lol:

Can you measure the gap at 12" intervals and post here?

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Fri May 03, 2019 8:53 am
by icelikkilinc
You have invested a lot in this boat - not only financially but romantically I would say :D
You saved the hull to start with rather than starting over :wink:

If I would you, not to be upset that you have not done it in future(might not affect the performance, more on personal satisfaction), I would fix this now at this stage.

Not with fairing compound, that kind of required thickness should not be achieved by fairing, more structural bond would be good.
Try to create a mold where you can pour a self leveling compound from epoxy.
draw lines on guide rails on how much you need to fill.
create a loose mix of epoxy and wood flour and use as the level compound.
After fully cured, measure and sand to achieve the desired angle.

Than you can think of fairing compound and next steps.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Fri May 03, 2019 9:04 am
by OrangeQuest
It looks like the board is touching at the transom and then touching again somewhere close to the post behind the boat. Between those two points it is not touching, at least that is what it appears in the pictures. Where you are getting it to rock is a bump or high spot. What TomW1 is talking about is the "hook" or dip between the post and the transom. That slight dip before the transom will cause the transom to push the back of the boat up and at the same time push the bow down. The boat will ride more level with having to use less trim. It is very slight and you would not notice the effects at all without precision measurements. If you were wanting all out speed then you may want to correct it and gain that .05 mph faster! :wink:

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Fri May 03, 2019 10:16 am
by BB Sig
I zoomed in and I see what you are saying but it looks like it is a piece added on. I think we need a closer picture of what is catching on the transom. :?

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Fri May 03, 2019 2:27 pm
by Fuzz
I have a boat with some rocker in it. I am not sure how it compares to yours but I know what it does no mine. When on plane it lifts the bow. At some point you get enough bow lift to cause porpoising. Mine is made worse by having too much stern weight.
You know it is there and it bothers you so I would fix it now. It looks like you could get most of it out by bonding a piece of 1/4 plywood to the stern. you will use a lot less filler that way.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Fri May 03, 2019 2:30 pm
by Jaysen
Why use play and not 1708?

Honest question.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Fri May 03, 2019 2:56 pm
by Fuzz
Jaysen wrote: Fri May 03, 2019 2:30 pm Why use play and not 1708?

Honest question.
It would take 6 layers of 1708 to make 1/4 inch thickness. That is a lot of glass and epoxy. I am thinking to get close with plywood and then glass ,fill and fair.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sat May 04, 2019 6:01 pm
by TomW1
Tom I was seeing light under your straight edge and thus my answer. Sorry for the confusion. The newly posted pictures reflect what you have and I agree with Fuzz. Add a 4" piece of 1/4 " at the transom and fair it in. A piece or two of 6" tape to hold it to the transom and you are all set.

Again sorry my eyes misread the original photo.

Tom

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Mon May 06, 2019 4:30 am
by TomTom
Thanks - it is actually quite confusing - I can get the straight edge to lay "straight" for about the rear 3.5 feet. But it rocks at this point and if I let it rock and lay towards the bow, there is about a 3/8" gap at the transom.

The plywood you see was a "mold" to lay the straight edge against and find the optimum position where I could get the longest "straight" section beyond the bulge.

I have gone with Fuzz's suggestion - of sorts - and used wood - I have actually ripped cedar strips in tapers and glued them down.

Today the sander/ polisher is out.

I will post a pic when it is done.... Sounds complicated I know - but I have always been intrigued by strip planking and plywood is so hard to get here...

This whole thing has been a learning curve...

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Mon May 06, 2019 1:16 pm
by Fuzz
The tapered strips will work just as good or even better :D I am sure you will put this little deal behind you soon.

Re: C19 - Major Structural Issues Now Slowly Getting there - Stretching to 21 now!

Posted: Sun Aug 04, 2019 10:21 am
by TomTom
Herewith some progress on the C19 stretch ... I used tapered strips of cypress in a similar manner to strip planking to get rid of the rocker that had formed when I extended my hull... It is lighter and easier to fair that layers of fiberglass.

It received a final piece of biaxial and then I have attached the spray rails, strakes and the skeg. The skeg will be squared off and then have a sacrificial piece of lumber screwed to it... I think it will make steering at slow speeds much easier.

Now onto the QuickFair and hopefully she will be ready to paint soon...

Image

Image


Image

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Aug 04, 2019 10:36 am
by TomTom
A few more pics...

Image

Image

Image

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Aug 04, 2019 11:48 am
by piperdown
Wow 8O that's a lot you have accomplished! Looking good! :D

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Aug 04, 2019 12:25 pm
by Fuzz
It is good to see you are making progress with your repair/stretch :wink:

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Aug 04, 2019 12:41 pm
by TomTom
Yup I am pleased with it ... just too scared to tell the boss that it might have been a little more than 10%!

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Aug 04, 2019 9:04 pm
by fallguy1000
Did you glass over the cypress? I'd be a bit nervous about leading edge delam. I just don't trust thin wood.

It is looking good.

I don't envy you and wishin you the best outcome.

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Aug 05, 2019 12:42 am
by TomTom
Yup - has another layer of biaxial 450 over that section.

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Aug 06, 2019 8:13 am
by fallguy1000
TomTom wrote: Mon Aug 05, 2019 12:42 am Yup - has another layer of biaxial 450 over that section.
This is good..

You seem to be making good decisions here. Forgive me if I sound patronizing. I think things will go well is all I am trying to say.

What epoxy did you use again?

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Aug 06, 2019 5:46 pm
by TomTom
Ampreg 21 by Gurit

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Aug 06, 2019 10:00 pm
by fallguy1000
TomTom wrote: Tue Aug 06, 2019 5:46 pm Ampreg 21 by Gurit
Good stuff ?

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Aug 06, 2019 11:37 pm
by TomTom
Yes - its been great - being replaced my Ampreg 30 - its what I can get here. Meant to be more environmentally friendly and less allergic reactions.

They also do SP106 which is more suitable for wooden boat building and which is being replaced by Ampro - and its also very nice - but hard for me to get here.


https://www.gurit.com/-/media/Gurit/Dat ... erview.pdf

Re: C19 Stretch and re-build Progress Report Pictures and Engine Mounting Advice Sought ...

Posted: Fri Jun 05, 2020 12:34 pm
by TomTom
Hi Everyone - I know it’s been a while since I last posted. Lots been going on including the birth of my first child - Kiara - a lovely little girl in February this year - and I am smitten! She’s 4 months and already has Daddy wrapped around her finger!!

I have made slow but steady progress on my C19 extension/ rebuild! It’s quite a bit longer than the boss man suggested but I have added two extra frames, my stringers are a bit taller, my cleats bigger, and there is more glass - so I think she’ll be alright!

Will post some pics of the whole process when I get over the next hump. There are some things that I did differently that I am pretty pleased about.

I decided to mount the engine I am going to put on her - which is a 2012 Yamaha 4 stroke 150. I have made the transom wide enough for twins - because in my part of the world people like twins and if I ever sold her she would do better with this layout.

I also decided I want to be as close to the back of the boat as possible when fighting a fish - especially as the engine is quite tall.

I don’t know what the term is for this “design” but I wanted a motorwell lay out where I could have some storage/ kick lures and stuff out of the way.

Finally, and without opening a can of hate mail from all you amazing builders who have achieved no issues with chase tubes! :D :D but I did not want chase tubes anywhere under the sole where I could not see them because I have yet to find a way to glue them really well between frames. (As a side note I have been building a few bamboo backed longbows and been using West’s G-Flex epoxy which sticks like hell to the plastic cups I use for mixing - so this may be the way to do it - but I have been bitten in the past by leaking chase tubes and I am in no mood to pull up another sole on a boat!!) 😂😂


We are all shaped by our own experiences ... but I feel like running chase tubes all over the place is borrowing trouble... so I have left all the compartments in the middle without foam and I plan to have lids that I can screw down against a rubber gasket (a piece of surgical tube in a half round grove). I am modifying a design I saw on Russel Brown’s website that he uses for kayak lids.

The idea is that I will still have a self-bailing deck but if I need to check below deck then removing a few screws will be enough to have an inspection.

The rigging will still run in tubes - but these will all go down the Center of the hull.

Anyways ... here are some pics.

I wanted some thoughts on how best to run the cables up to the engine and how much clearance I should have in front of the engine for the cables. I have hydraulic steering - but I believe the throttle/ gear cables need an 8” radius?


Image

So the blue lines are where my rigging will run... in PVC tubes...

Here are some mock ups of what I am thinking motorwell wise ...

Image

The arrow is indicating this “bulkhead” is 8 inches deep. There is 14 inches below that to the floor. Enough I think to be a worthwhile space. But wondering if I could make the bulkhead 6 inches or less?

Image

This is the engine fully trimmed up. Do I have enough space for the rigging? It goes into that black “nipple/dingdog” sticking out (my engine identifies as Gender Neutral Btw!!!). There is about 7 inches between there and the plywood in this pic.

The arrows indicate that the “bulkhead” is 26 inches from the transom and there is 6 inches to the box on the side.

Here are some more images...

Image

Image

Re: C19 Stretch and re-build Progress Report...

Posted: Sat Jun 06, 2020 1:04 am
by Fuzz
I was wondering how you were doing. The boat is looking good you have made great progress.

Re: C19 Stretch and re-build Progress Report...

Posted: Sat Jun 06, 2020 8:17 am
by fallguy1000
Not much help on the bulkhead question. Generally, a bh can be made a bit smaller if it is glassed heavier and surrounding tabbing is made wider.

Congrats on the birth of your child.

Re: C19 Stretch and re-build Progress Report...

Posted: Sat Jun 06, 2020 8:46 am
by TomTom
Here are a few more pics ... trying another system to get enough space in front of the engine for the cables - this has about 8 inches Fwd and down. I think it’s enough. That shorter step can go up much higher to level with the sides of the boat and have a small vertical cut out to take the engine at full tilt. I could do away with the next horizontal section and vertical piece. This would get me closest to the back of the boat. About 20 inches.

Or I could raise the back step and put a covering board/ gunwale across the two vertical sections. I would have to cut out a little bit in the Center for the engine but I would then have useable a long box horizontal box which could be some useful storage space and I could also mount some rod holders through it.
This puts me a little further from the back of the boat but gives me more space underneath.


Still thinking!!

Image

Image

Image

Re: C19 Stretch and re-build Progress Report...

Posted: Sat Jun 06, 2020 4:20 pm
by Fuzz
Is it just the picture or is the transom where the motor is really thin? It looks like it is only 18mm or so :doh:

Re: C19 Stretch and re-build Progress Report...

Posted: Sat Jun 06, 2020 4:30 pm
by TomTom
Transom is whatever the C19 spec was. Can’t actually remember - I think it’s 3x 12 mm or something like that. I used the old one. But I can see that it looks very thin in the photo. I do think it’s thin compared to a lot of transoms.

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Jun 07, 2020 2:04 am
by TomTom
Image

Image

Image

Image

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Jun 07, 2020 2:09 am
by TomTom
Image

Image


One thing I did which I am really happy about was glue my sole down in individual and alternating sections to make sure that each and every compartment was properly sealed. This way I could check the glue line on each one. I don’t believe this is easy to do with bigger sections.

Image

Image

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Jun 07, 2020 7:58 pm
by Fuzz
You have made soon really good progress. She will be back in the water and better than ever pretty soon :D I see in the new pictures how the transom was built. The one before just deceived my eyes. After the deck problems you had I sure do understand why you are doing the deck different. I can see how it is easier to be sure you have things glued down and well sealed.

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Jun 09, 2020 6:18 am
by OneWayTraffic
Question about the sole: How are you going to stop it from seperating and flexing? I know there was a FS17 with a sole butted on a cleat (no butt block) and glassed over. It eventually seperated over the join.

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Jun 09, 2020 11:39 am
by TomTom
OneWayTraffic wrote: Tue Jun 09, 2020 6:18 am Question about the sole: How are you going to stop it from seperating and flexing? I know there was a FS17 with a sole butted on a cleat (no butt block) and glassed over. It eventually seperated over the join.
Hmmm - interesting - was the sole butted over several compartments or did each compartment have its own “lid” so to speak?

Also were the compartments foam filled or not? I believe unfoamed compartments contract and expand a lot.

I am not saying my way is the right way to do it - but my cleats are 2X2’s ripped diagonally and I have added 450 gsm cloth over all of this - Maybe I should tape the seams too if what you are saying is true.

But to me it just feels to be like a more certain way of knowing each individual compartment was sealed properly. I got to inspect each glue line around each compartment because I glued the compartments up in a checker board fashion.

And I guess if cracks do appear at least I know exactly which compartments I need to deal with. There are no chase tubes to help water get from one end of the boat to another, and if a crack were to appear I would know which section to fix and not worry that there could be 3 or 4 compartments with water in there.

I have seen water move by a sort of capillary action between compartments (admittedly on a boat that didn’t have the stringers or frames glassed in) - it was on my OD 18 - and the plans just called for the stringers to be glued to the bottom of the boat. Maybe I did a crap job of gluing. Or maybe without glass it’s really really hard to make sure there are no hairline places for water to pass?! Either way, gluing a sole down on top of a maze of stringers and frames is no different to glueing a maze of stringers and frames onto the bottom panel of an OD 18 - in as much as there is no glass there to mitigate a poor bond or glue line?

Ever put really runny superglue in a hairline crack in wood? Amazes me to watch how far it can get sometimes.

The truth is how many people open their boats up once they are made and see whether water got in or not?

For better or worse I am in the unenviable position of having had to do a full and thorough investigation of how water can get all over the place under a sole on a boat that to all intents and purposes felt solid and well built.

I believe there was a DE25 (Matt Gent?) that had been “professionally” built and water somehow got in through some scupper pipes.

At least this way I feel I can isolate the issue.

Time will tell if it’s a good system.

These forums are a wonderful resource base for different ideas and theories - for what it’s worth this is mine!

I will think about taping those seams after your comments - but I am happy with the principle behind my plan!!

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Jun 09, 2020 9:03 pm
by OneWayTraffic
It's clear that you've thought about it at least.

My freakish memory --for remembering random stuff only!-- allowed me to dig up this post I read from 6 years ago. Designlady's FS17.

https://forums.bateau2.com/viewtopic.php?f=2&t=58864

The joins were sitting on the cleats, no butt blocks or splices under. Then the pine cleats split along the grain.

I know SideSlippa did it a similar way, but glassed each one individually sitting in between the frames then glassed over the whole sole with biaxial.

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Jun 09, 2020 9:23 pm
by TomTom
Thanks for this - had not thought about the cleats splitting as a possibility must admit! Will have a good read through.

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Jun 09, 2020 9:36 pm
by OneWayTraffic
https://forums.bateau2.com/viewtopic.ph ... &start=210

Sideslippa's boat. Go back a page for pictures. No issues with the layout I am aware of, though he stopped posting on the forum.

Edit: From my reading you have already glued the pieces in and glassed over the sole? If so I'd probably put another layer of glass on and call it a day. You have a big boat. If the sole pieces are not yet in, is it possible to tape over the cleats to lock them in place?

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Jun 10, 2020 1:53 am
by TomTom
OneWayTraffic wrote: Tue Jun 09, 2020 9:36 pm https://forums.bateau2.com/viewtopic.ph ... &start=210

Sideslippa's boat. Go back a page for pictures. No issues with the layout I am aware of, though he stopped posting on the forum.

Edit: From my reading you have already glued the pieces in and glassed over the sole? If so I'd probably put another layer of glass on and call it a day. You have a big boat. If the sole pieces are not yet in, is it possible to tape over the cleats to lock them in place?
Yes interesting read - I wasn’t quite sure but it seems that the sole was joined using a 1x3 inch cleat and no butt block? And the cleat wasn’t above a stringer/ frame?

I am sincerely hoping that because my joints are at cleats that are attached to stringers/ frames this isn’t likely... but had a slightly restless night of the old BBB (Boat Builder’s Brain) running scenarios over and over in my head...

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Jun 10, 2020 3:50 am
by OneWayTraffic
I would run it by the resident designer/engineer to be sure. I think that the splice was on a cleat on a frame or stringer. It’s not too late to place a layer of 6mm over the whole kit. Or glass sufficiently that it won’t matter.

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Jun 10, 2020 3:53 am
by TomTom
Thanks OneWayTraffic - I read Sideslippas post - did he have any issues with his method that you recall?

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Jun 10, 2020 7:10 am
by OneWayTraffic
Check his post history, I do not recall any. He did overpower it (90hp) and take it offshore. But it was overbuilt. I looked into his in detail, as I have also tabbed my frames in before inside glass, though not for the same reasons.

edit:
sideslippa wrote: Thu Feb 07, 2013 8:11 am I can recommend the OB17 personally to do what you want and more. It is stable, unsinkable, and versatile, I have been 20 mile offshore regularly and also use it in rivers and lakes and does go in quite shallow water. I have been off shore in ordinary and rough conditions of 15-20 knots breeze on a few occasions. It is slow in these seas at 6-8 knots but completely safe. In 10 knots and under wind conditions in open water it can travel up on the plane especially in following seas. If you built light and simple I believe a 50 HP would do the job OK. I have a 90HP which is really nice with great holeshot and 35 Knots top end but it is not needed with most driveing at only half power or less. Minimum plane speed is 12 knots. Very smooth transition to plane. Very good manners in following seas even quatering...it tracks straight with no broach tendencies. Good fuel eoconomy too. Only regret maybe is that if i did it again I would build the OB19

Cheers!
His very last post on here.

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Jun 10, 2020 7:26 am
by OneWayTraffic
TomTom wrote: Wed Jun 10, 2020 1:53 am

Yes interesting read - I wasn’t quite sure but it seems that the sole was joined using a 1x3 inch cleat and no butt block? And the cleat wasn’t above a stringer/ frame?

I am sincerely hoping that because my joints are at cleats that are attached to stringers/ frames this isn’t likely... but had a slightly restless night of the old BBB (Boat Builder’s Brain) running scenarios over and over in my head...
I believe that you are right, it was a cleat hanging in mid air. Flex downwards would stress the lower edge of the cleats. Hopefully that shouldn't happen if the cleats are fixed. I wouldn't know for sure. You said you have 400g biax over the lot? If the cleat is fixed to a frame then it would normally be under tension at the top surface by the frame. In the middle of the span it's reversed, the underside is in tension. I've seen this in a boat design book, I can draw or find a diagram if you like.

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Jun 10, 2020 7:35 am
by OneWayTraffic
frame forces.png
frame forces.png (3.29 KiB) Viewed 1398 times
This was how I remembered it, from some old book on fibreglass boat design. The forces switch near the framing member.

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Jun 10, 2020 8:54 am
by TomTom
I remember SideSlippa did inbuilt reverse chines as well I think. Was a nice boat. I looked at the OB quite hard once.

I think you are right about the forces. Glass is good in tension - so worst case is I add more on top!

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Jun 10, 2020 11:03 am
by TomTom
Gonna rest easier now that Jacques has commented on this!

Moving on to hatch routing now.... a router is such a cool piece of kit once you get your head around it.

A router, an oscillating multi-tool and a variable speed sander/ polisher have to be 3 of my most under rated boat building tools until I started figuring out how useful they are!

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Jun 10, 2020 1:08 pm
by BrianC
TomTom wrote: Wed Jun 10, 2020 11:03 am ...a router is such a cool piece of kit once you get your head around it.
I have a 1/2" shank router that I use to pre-shape edges — I have it set up on a router table and it works well that way. I've tried using it free hand but it is just too big; it aways gets away from me at some point and digs holes that I end up spending hours to fix.

I've been thinking about getting a small trim router for hinge cuts, etc. Which one do you find works best for the fine finish work?

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Jun 10, 2020 1:45 pm
by TomTom
I have a Makita RP0900 - it’s a smallish machine - but it does what I need it to do. Not sure where you are based but I have always found Makita a solid power tool.

Re: C19 Stretch and re-build Progress Report...

Posted: Thu Jun 11, 2020 9:53 am
by pee wee
I've got two big routers, one medium and one trim router, then I bought this kit:

https://www.amazon.com/Bosch-PR20EVSNK- ... B000EJX202

It's now the router I reach for 80% of the time. I don't use the attachments very often, but the offset base comes in handy on occasion.

Re: C19 Stretch and re-build Progress Report...

Posted: Thu Jun 11, 2020 10:21 am
by joe2700
pee wee wrote: Thu Jun 11, 2020 9:53 am I've got two big routers, one medium and one trim router, then I bought this kit:

https://www.amazon.com/Bosch-PR20EVSNK- ... B000EJX202

It's now the router I reach for 80% of the time. I don't use the attachments very often, but the offset base comes in handy on occasion.
Thats the router I've been using for the duration of my build as well, just bought it as a different kit that has a plunge base but not the angled or offset bases. Also highly recommend it. Plenty small for tight spaces but with the full size base on it has enough power to be a full size router for anything I do. When I was researching routers before buying it was widely regarded as one of the best.

Re: C19 Stretch and re-build Progress Report...

Posted: Thu Jun 11, 2020 1:28 pm
by TomTom
I would say that good router bits make a big difference. They also don’t like lumps of epoxy or fiberglass either so be careful with them!!

Re: C19 Stretch and re-build Progress Report...

Posted: Thu Jun 11, 2020 7:44 pm
by BB Sig
Ive been needing a small router. I think I found which one I need to buy...

Re: C19 Stretch and re-build Progress Report...

Posted: Fri Jun 12, 2020 2:37 am
by TomTom
Any suggestions for a way to “lock” these lids down - I want to put a surgical tube as a gasket in that routed section - then I want something that can squeeze and compress the lid against it.

Was thinking 4 screws with nuts embedded in epoxy because I want the fixture flush with the floor - but I figured there must be something more quick release.

I am trying to remember the name of those things that you push and twist - like a bolt with a horizontal pin that follows a spiral twist ... you push them in and twist and they lock...

Image

Re: C19 Stretch and re-build Progress Report...

Posted: Fri Jun 12, 2020 11:33 am
by joe2700
I think you are talking about a cam latch or compression latch.

Re: C19 Stretch and re-build Progress Report...

Posted: Fri Jun 12, 2020 2:38 pm
by TomTom
Was thinking more something like these https://store.pyiinc.com/collections/fl ... 3943241729

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Aug 02, 2020 10:53 am
by TomTom
Thought I would put some progress pics up...

Nearly ready for paint...

Image

Image

Image

Here’s how she was before...

Image

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Aug 02, 2020 2:20 pm
by Dan_Smullen
Almost ready for more blue water action!

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Aug 02, 2020 3:10 pm
by TomTom
Dan_Smullen wrote: Sun Aug 02, 2020 2:20 pm Almost ready for more blue water action!
I can’t wait. Might even start sharpening some hooks!

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Aug 03, 2020 2:13 am
by Fuzz
The boat looks good stretched. It is going to look real good with a little paint on it.

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Aug 03, 2020 2:56 pm
by TomTom
Yeah. I am still worrying whether I should have the console a bit further fwd. It looks good where it is and space is right. But I know us fat boys all gravitate to the back!

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Sep 27, 2020 3:24 pm
by TomTom
Well ... I launched her today to draw the waterline and see if she floats. Interested to know what everyone thinks. She draws 8 inches at the transom with 3 people on board and 100 litres of fuel. Maybe console could have been a tad further fwds but would have been a pain to move bulkheads around to make the space under the console correct. And I think with the front locker loaded with stuff she should sit about right.

Here are some pics...

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Sep 27, 2020 4:52 pm
by Fuzz
Boat seems to be sitting really light in the bow. But then again the whole boat looks to be really light on the water.
Seeing you in the boat really shows its size. That thing is huge :D

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Sep 27, 2020 9:55 pm
by Dan_Smullen
She’s looking great!

What is the location? Freshwater or salt?

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Sep 27, 2020 10:12 pm
by fallguy1000
Dan_Smullen wrote: Sun Sep 27, 2020 9:55 pm She’s looking great!

What is the location? Freshwater or salt?
Namibia or South Africa. Salt.

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Sep 27, 2020 10:13 pm
by fallguy1000
Did she porpoise?

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Sep 28, 2020 8:18 am
by TomTom
Dan_Smullen wrote: Sun Sep 27, 2020 9:55 pm She’s looking great!

What is the location? Freshwater or salt?
Indian Ocean - salt water - East Africa - near Mombasa.

Haven’t connected the engine to test. Was just painting the water line for antifoul.

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Sep 28, 2020 9:11 am
by BB Sig
Nice test! She looks good in the water. :D

How did she handle the wind? :lol:

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Sep 28, 2020 12:07 pm
by TomTom
I put a small skeg on her - she seems to get blown around less! Not quite sure if she needs a bit more weight fwds.

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Sep 28, 2020 5:44 pm
by OneWayTraffic
Should ride like a Tolman Widebody. They are commonly stretched to 21' as well.

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Sep 28, 2020 8:12 pm
by Fuzz
OneWayTraffic wrote: Mon Sep 28, 2020 5:44 pm Should ride like a Tolman Widebody. They are commonly stretched to 21' as well.
If it does that is a good thing. Living in Tolman's back yard there are a ton of them here. They have a darn good reparation :wink:

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Sep 28, 2020 8:24 pm
by Dan_Smullen
TomTom wrote: Mon Sep 28, 2020 8:18 am
Dan_Smullen wrote: Sun Sep 27, 2020 9:55 pm She’s looking great!

What is the location? Freshwater or salt?
Indian Ocean - salt water - East Africa - near Mombasa.
Water looks amazing. Fishy too. 8)

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Sep 28, 2020 11:31 pm
by TomTom
Dan_Smullen wrote: Mon Sep 28, 2020 8:24 pm
Water looks amazing. Fishy too. 8)
It’s a pretty good part of the world! Went out yesterday with a friend and we got 16 yellowfin and 2 wahoo. Now feel like I’ve been using a fairing board :) :)

Old vs new ...


Image

Image

Does anyone think I should move the console slightly fwd? It’s not been fixed yet. It will be a bit of a pain to do because I have mounted the base plates for the T Top. But I am worried she is a little heavier in the stern. I have a 100 lts ballast where the fuel would go and the batteries in their place but nothing in the front locker.

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Sep 29, 2020 12:22 am
by fallguy1000
TomTom wrote: Mon Sep 28, 2020 8:18 am
Dan_Smullen wrote: Sun Sep 27, 2020 9:55 pm She’s looking great!

What is the location? Freshwater or salt?
Indian Ocean - salt water - East Africa - near Mombasa.

Haven’t connected the engine to test. Was just painting the water line for antifoul.
Do you mind me asking? How does one make a living in East Africa?

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Sep 29, 2020 4:35 am
by TomTom
Travel and tourism is our business - so things are a bit tough right now! Farming is also a big business for many people. Coffee, tea, cut-flowers, market vegetables.

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Sep 29, 2020 4:55 am
by OneWayTraffic
Fuzz wrote: Mon Sep 28, 2020 8:12 pm
OneWayTraffic wrote: Mon Sep 28, 2020 5:44 pm Should ride like a Tolman Widebody. They are commonly stretched to 21' as well.
If it does that is a good thing. Living in Tolman's back yard there are a ton of them here. They have a darn good reparation :wink:
I have the book; needed to order it direct from the USA. I converted the offsets to metric and put them into a spreadsheet next to the C17 and some other Merten designs. The deadrise, width at the chine is almost identical between the C17 and widebody. The Tolman has a little more flare in the sides, though not as much as the FS17. The widebody is not pinched at all in the stern while there is minimal pinching to the C17. The C19 is a little wider of course. Since some Tolman widebodys are stretched from anywhere from 21 to 26+ feet with decent performance I'd expect that this stretch will have little effect on the performance. Possibly it will plane heavy loads better.

At the end of the day, I found the instructions a little hard to follow for the Tolmans: the need to hang and scribe side panels, the many imperial-metric conversions, and the references to materials and fasteners available only in the USA clinched it for me. Still it's a great book and I've gotten a lot of good advice and hints from it. My scuppers for example is one, as are the cabin and hardtop options which made me believe I can fit something like that into a C17, as long as I don't get excessive.

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Sep 29, 2020 4:56 am
by OneWayTraffic
TomTom wrote: Tue Sep 29, 2020 4:35 am Travel and tourism is our business - so things are a bit tough right now! Farming is also a big business for many people. Coffee, tea, cut-flowers, market vegetables.
This too will pass. Soon I hope.

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Sep 29, 2020 11:36 am
by TomTom
Yes - to be fair there are worse places to be stuck!

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Sep 29, 2020 1:55 pm
by TomTom
I had a look at the water line vs the level of the floor and she is about an inch high at the bow. Any guesses how much weight in the bow locker would one need to level this off?

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Sep 29, 2020 3:07 pm
by OneWayTraffic
PPI for your upscaled version should be ballpark 190kg per inch. Maybe quarter to half that at the bow? Less if you move weight from all the way back to all the way forward.

Calculating that would be troublesome due to increasing volume as you immerse the bow. Jaccques could tell you for sure, but he'd need to model the hull extension.

Or you might just not worry about it.

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Sep 29, 2020 3:39 pm
by TomTom
I suppose we could just put more cold beers at the front!

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Sep 29, 2020 4:20 pm
by BB Sig
TomTom wrote: Tue Sep 29, 2020 3:39 pm I suppose we could just put more cold beers at the front!
Now you're talking! :lol:

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Sep 30, 2020 3:04 pm
by TomW1
TomTom just move the console forward an amount to offset the weight to offset the weight of the motors and any other weight you shifted back by your extension. So weight of motor and other = 400lbs x 1.5ft = 600lbs That means you have to move 600lbs forward of the old center of gravity. This is an example as I don't recall exactly how much you added to your C19, 1 or 2 feet.

Your new center of gravity will be about 42t, an% from the transom at the waterline. Just as the C19's was. So all your weight will need to be balanced around the console on that line or just forward of it. So remember the formula if you move 10lbs forward 10ft that is equivalent to moving 100lbs forward.

Uhm, a case of beer + ice forward of the console- 50lbs * 3 = 150 sounds good to me. :D

Good luck friend, having fun watching your build as usual.

Tom

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Sep 30, 2020 11:35 pm
by TomTom
Thanks TomW ... I think I would move console fwd If it was easier ... but where it is now looks best aesthetically, but moreover if I move if further fwd I would have to cut out and move one frame as well so the front of the console matches that frame and also I would have to cut up sole and move the T top mounting plates fwd. It’s not a huge job, but I had kind of carried on with the assumption it was “about right”.

When we go off-shore I keep an 8 HP kicker engine in the front locker. I also have an anchor. And sometimes 1000 foot of rope.

I can also keep fuel up front as I use portable Jerry

Re: C19 Stretch and re-build Progress Report...

Posted: Thu Oct 01, 2020 2:07 am
by TomW1
TomTom wrote: Wed Sep 30, 2020 11:35 pm Thanks TomW ... I think I would move console fwd If it was easier ... but where it is now looks best aesthetically, but moreover if I move if further fwd I would have to cut out and move one frame as well so the front of the console matches that frame and also I would have to cut up sole and move the T top mounting plates fwd. It’s not a huge job, but I had kind of carried on with the assumption it was “about right”.

When we go off-shore I keep an 8 HP kicker engine in the front locker. I also have an anchor. And sometimes 1000 foot of rope.

I can also keep fuel up front as I use portable Jerry
Okay Tom, don't worry about the console. Just do the weight calcs so that you know you are floating level as you leave the dock or as level as you can get that fancy new boat. :D She will ride and handle best if she is balanced. People are going to move around and throw the balance off any way, but at least you know your boat is as good as you can make her. :lol:

Tom

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Oct 04, 2020 2:57 am
by TomTom
A few updates.

1) I have glued a fitting onto the long elbow of my chase tubes using GFlex epoxy. This means should any water get in the chase tube I can drain it into the bilge

Image



2) I think my rubber gaskets using latex tube are going to work well to seal my compartments that’s I still want partial access to
Image


3) I’ve been looking at the west system method of bonding bolts and nuts. I want to be able to screw down my lids on these compartments against this rubber gasket ... I also want to embed a nut. I like the west system of lining everything up with a pilot hole at the bottom... but I worry about water ingress right and the bottom ... and also surely this would be stronger if the nit was under a layer of epoxy

Image

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Oct 04, 2020 10:13 am
by fallguy1000
TomTom wrote: Sun Oct 04, 2020 2:57 am A few updates.

1) I have glued a fitting onto the long elbow of my chase tubes using GFlex epoxy. This means should any water get in the chase tube I can drain it into the bilge

Image



2) I think my rubber gaskets using latex tube are going to work well to seal my compartments that’s I still want partial access to
Image


3) I’ve been looking at the west system method of bonding bolts and nuts. I want to be able to screw down my lids on these compartments against this rubber gasket ... I also want to embed a nut. I like the west system of lining everything up with a pilot hole at the bottom... but I worry about water ingress right and the bottom ... and also surely this would be stronger if the nit was under a layer of epoxy

Image
It looks good, but I think a hole might suffice and water can just run out.

The location of the chase entries is the real cuprit; they should be high and not on horizontals.

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Oct 04, 2020 10:16 am
by fallguy1000
Also, the hatches need drains. For mine, I installed nylon fitting with hose barbs and ran the hoses to thru hulls. For you; it can go to wet bilge if that is a dry locker.

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Oct 04, 2020 10:18 am
by fallguy1000
Put any nylon fitting on the stern side here.
8072A5FD-087B-48C2-AD7A-5441097BD7A4.jpeg

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Oct 05, 2020 1:42 am
by TomTom
fallguy1000 wrote: Sun Oct 04, 2020 10:18 am Put any nylon fitting on the stern side here.
8072A5FD-087B-48C2-AD7A-5441097BD7A4.jpeg
I was hoping that screwing the hatches tight against the gasket would be enough without a drain. They are “semi-permanent”.
I can drain each individual locker into the wet bilge. Each one has a separate pipe that goes to the bilge and has a plug.

Has anyone had any luck bedding self tapping screws in epoxy and removing/ retightening them?

Otherwise I am thinking of bedding something like this....

I think they are called furniture sleeves.

Image

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Oct 05, 2020 5:50 am
by Browndog
In the US they are called T-nuts. A few guys on the forum have used them on their builds.

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Oct 05, 2020 8:54 am
by fallguy1000
You can use adjesive head nuts as well or make your own with a drilled plate and welding. I also trapped nuts inside epoxy by waxing the bolt heavily, then drawing it in and then applying thickened epoxy with a tongue depresser to all 6 edges and a circle of epoxy around.

I think your lockers will work better with drains where I drew. Rain is insidious and will find a way around your seals of the pressure gets high. By creating a path to the bilge; you will probably only get a few drips in there.

The bigger problem is mildew attacks things so bad and dampness once inside will not leave.

Nylon hose barb nuts work well. You can get variousbthreads on them and a piece of clear tube to route water away and keep the box pretty dry.

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Oct 05, 2020 9:31 am
by joe2700
TomTom wrote: Mon Oct 05, 2020 1:42 am
I was hoping that screwing the hatches tight against the gasket would be enough without a drain. They are “semi-permanent”.
I can drain each individual locker into the wet bilge. Each one has a separate pipe that goes to the bilge and has a plug.

Has anyone had any luck bedding self tapping screws in epoxy and removing/ retightening them?

Otherwise I am thinking of bedding something like this....

I think they are called furniture sleeves.

Image
Not self tapping screws. I've had luck embedding a nut in epoxy, using a well waxed machine screw that can be removed once cured. I've also recently had luck epoxying g10 in place, then drilling and tapping the g10.

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Oct 05, 2020 11:23 am
by TomTom
joe2700 wrote: Mon Oct 05, 2020 9:31 am

Not self tapping screws. I've had luck embedding a nut in epoxy, using a well waxed machine screw that can be removed once cured. I've also recently had luck epoxying g10 in place, then drilling and tapping the g10.
What is G10?

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Oct 05, 2020 1:10 pm
by joe2700
TomTom wrote: Mon Oct 05, 2020 11:23 am
What is G10?
Epoxy/fiberglass laminate that is cured under high pressure so it is very dense. Can be purchased in sheets, rods, tubes. The more modern designation is often FR-4 but in boatbuilding I usually still see it referred to as G-10.

https://www.jamestowndistributors.com/u ... o?pid=8758

https://www.mcmaster.com/garolite

It's great for backing plates or other high load applications and it's also machinable so it takes threads. I just did a test for my hatches recently and the impact driver stripped the 8-32 machine screw before the hole I drilled and tapped was damaged.

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Oct 05, 2020 2:29 pm
by TomTom
Wow! Sounds interesting! I will have a look!

Re: C19 Stretch and re-build Progress Report...

Posted: Sat Oct 10, 2020 1:55 pm
by TomTom
Image

Re: C19 Stretch and re-build Progress Report...

Posted: Sat Oct 10, 2020 1:58 pm
by TomTom
Image

Re: C19 Stretch and re-build Progress Report...

Posted: Sat Oct 10, 2020 4:54 pm
by joe2700
TomTom wrote: Sat Oct 10, 2020 1:58 pm A few more images of my extension...



[imgur2] https://i.imgur.com/uVjwiQr.jpg[/imgur2]

[imgur2] https://i.imgur.com/vWSAsFF.jpg[/imgur2]

[imgur2] https://i.imgur.com/zbsFc4z.jpg[/imgur2]
For imgur links you just put the random letters inside the brackets instead of the entire link. The part between "imgur.com/" and ".jpg".

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Oct 11, 2020 1:09 am
by TomTom
Thanks - that’s still not working for me using the imgur icon But I have worked out that I can adjust the image size as follows ... https://superuser.com/questions/1238552 ... mgur-image ....and before the images were too big to link as images ... so this should work now!

Image

Image

I wanted to be as close to the back as I safely could. With a big 150 HP I have had to make a little cut out for it to tilt fully up. I will put a gunwale across that’s wide enough to take 2 rod holders ...

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Oct 11, 2020 5:46 pm
by Dan_Smullen
Nice work re-gaining more deck space. After the stretch, it pays to get the most out of it.

She's gonna fly...

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Oct 11, 2020 11:17 pm
by TomTom
Fuzz wrote: Mon Sep 28, 2020 8:12 pm
OneWayTraffic wrote: Mon Sep 28, 2020 5:44 pm Should ride like a Tolman Widebody. They are commonly stretched to 21' as well.
If it does that is a good thing. Living in Tolman's back yard there are a ton of them here. They have a darn good reparation :wink:
Does anyone know if the Tilman’s were a constant or variable deadrise design? I see the later ones also had chine flats.

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Oct 21, 2020 9:05 pm
by Dan_Smullen
Hey Tom! A little off topic, but do you have any pics of your fuel tank set up? I’m interested in where you routed the fill hose.

Re: C19 Stretch and re-build Progress Report...

Posted: Thu Oct 22, 2020 11:49 am
by TomTom
Dan_Smullen wrote: Wed Oct 21, 2020 9:05 pm Hey Tom! A little off topic, but do you have any pics of your fuel tank set up? I’m interested in where you routed the fill hose.
Hi Dan will post pics when my chase tubes are glued in, but we just use vertical plastic 25lt Jerry cans for fuel. They sit upright in the Center compartment under the console and two sit side by side. I can fit 8 sitting vertically under the console. There are no gas pumps on the water here so we buy all our fuel on land, so it makes sense just to carry the Jerry can onto the boat and don’t have to siphon/ transfer fuel anywhere. It also means you are unlikely to run out of fuel as you have to switch tanks a few times a day! And it makes weight and balance distribution easy. It’s a simple solution but it seems to work fine for us. I may try a Y fitting between two tanks so we don’t have to screw and unscrew the intake straw and move it to the next tank as often.

Here is a picture of one...

Image

The fuel pipe goes in a chase tube all the way down the middle accessible compartments and then comes up through a pipe that is a few inches above floor height. Any water that gets into the chase tubes can be drained out because I have added a little plastic fitting that can be unscrewed if needs be.

Even if I did instal a permanent tank, I would have my filler cap at the console somewhere and not in the gunwale, then I wouldn’t have to run a chase tube through the stringers

Re: C19 Stretch and re-build Progress Report...

Posted: Thu Oct 22, 2020 9:45 pm
by Dan_Smullen
I asked for a fuel system pic, and I got it. Thanks!

I’ve been stuck on filling through the gunwale, but you got me off that. I’ve accepted that filling at the console is the best solution.

Short fill hose, no belly in the line, and easy to refuel while underway.

Thanks Tom. Back to the stretch!

Re: C19 Stretch and re-build Progress Report...

Posted: Thu Oct 22, 2020 10:41 pm
by TomTom
Dan_Smullen wrote: Thu Oct 22, 2020 9:45 pm I asked for a fuel system pic, and I got it. Thanks!

I’ve been stuck on filling through the gunwale, but you got me off that. I’ve accepted that filling at the console is the best solution.

Short fill hose, no belly in the line, and easy to refuel while underway.

Thanks Tom. Back to the stretch!
I’ve learnt - the long way round - that the simpler you can keep a boat the better. It will end up lighter and you will spend less time fixing things!

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Nov 15, 2020 8:10 am
by TomTom
Finally a bit of progress - some Jotun Penguard HB primer inside and out...

Image

Image

Image

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Nov 15, 2020 11:01 am
by cracked_ribs
That's looking really good!

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Nov 17, 2020 1:51 pm
by OneWayTraffic
TomTom wrote: Sun Oct 11, 2020 11:17 pm
Does anyone know if the Tilman’s were a constant or variable deadrise design? I see the later ones also had chine flats.
Tolman skiffs have nearly an identical hull shape to the C series boats. About 45 deadrise at entry, 10 degrees at transom. Constant deadrise over the last half of the hull. I have the book, and it's a good read. Main difference to the C series is that the stern is not pinched at all. The C series have a slight pinch. Because of that they are often stretched. The C17 is almost identical to a widebody (except for the chine flats) and the C19 would probably be similar to a shorter jumbo.

The important point is that Tolman skiffs are often stretched to any arbitary length. It doesn't seem to affect the properties of them much.

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Nov 17, 2020 10:44 pm
by TomTom
OneWayTraffic wrote: Tue Nov 17, 2020 1:51 pm
Tolman skiffs have nearly an identical hull shape to the C series boats. About 45 deadrise at entry, 10 degrees at transom. Constant deadrise over the last half of the hull. I have the book, and it's a good read. Main difference to the C series is that the stern is not pinched at all. The C series have a slight pinch. Because of that they are often stretched. The C17 is almost identical to a widebody (except for the chine flats) and the C19 would probably be similar to a shorter jumbo.

The important point is that Tolman skiffs are often stretched to any arbitary length. It doesn't seem to affect the properties of them much.
They have a very loyal following for sure. Jacques does too and rightly so. But maybe anytime you get your hands dirty for hours/ years on end with a project that preoccupies your mind you are invariably going to be passionate about what you built.

I have read a few stories/ posts about the Tolman’s and some great trips by their owners. Amazing fuel economy report (by a David Nolan who built a Jumbo 27) when compared to factory built boats doing the same overnight trips out for tuna.

I can’t help but wonder how much of this is due to weight being so much lighter than any inherent quality of hull design?

I believe there was a David Gerr article that basically summed up boat efficiency down to 1) weight 2) longer and leaner 3) efficient power source and all else is minor detail.... (I may be misquoting though)!



I also have the Novi 23 plans - which I believe is a “Variable Deadrise” or “Warped Plane” design. To my untrained eye the difference is very subtle between that and the C series. Yet I believe the Novi and DE builders report almost no planing hump. I am very curious about this subtle distinction, how it is achieved and why it isn’t taken advantage of more often.

I wonder whether the Tolman’s have a noticeable planing hump given they are a constant deadrise?

I am also curious why Tolman chose the constant deadrise?

In any case, whatever was decided I guess it worked because people do seem to love them.

I am also curious as to how the designs are lengthened. Do builders increase the bottom thickness and glass or simply add extra frames?

I am hoping to find out soon enough how mine will perform!

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Nov 17, 2020 11:43 pm
by cracked_ribs
I think the Gerr comment is pretty bang on...the Tolman is pretty similar to a C series. Relatively shallow deadrise, lightweight, not a ton of wetted surface, a little on the narrow side in some lengths, at least. That's a recipe for a low fuel bill.

If I had to guess, I'd say he went with a prismatic hull because it's easier to design, not to mention extend or expand. I think a warped plane needs to be tailored to its exact requirements more. I can knock off a prismatic hull bottom and feel pretty confident about what it will do. I wouldn't be confident about doing that with a warped plane.

I could be wrong but I think with a bit of weight forward on your boat and the extended hull, I don't think you'll see all that much bow rise either.

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Nov 18, 2020 1:45 am
by OneWayTraffic
Tolmans have a 12mm ply bottom. The ply is scarfed to length where needed. The front section is made from 2 layers of 6mm laminated. The ply is glassed both sides with 300gsm woven cloth and then there is some layers of woven tape at the keel and chines. There are two stringers only (ideally made from LVL) no frames. The sole is optional. The whole idea was to make a solid enough skin that the interior framing could be much reduced. Because there are no frames, the design is very modifiable. There's a Tolman forum on the net, where they talk about all those details.

The one thing I like is the thicker ply on the bottom. If I was doing my build over, I'd use 9mm ply over the back section of my boat, and 6mm on the front. In my build the 6mm ply sagged a bit between some frames, leading to a lot of fairing. Some of that was my own fault, as a long time went between planking and final glass.

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Nov 18, 2020 2:02 am
by Fuzz
The Tolmans were designed to give a good turn of speed and do so with low horse power. To do that they need to be kept light thus only two stringers and no framing. They worked and worked well but builders were not happy with the speed and started putting way more power on them than Renn had intended. The result was a number of them cracked the stringers. As they say you can't fix stupid. :help:

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Nov 18, 2020 2:11 am
by TomTom
Fuzz wrote: Wed Nov 18, 2020 2:02 am The Tolmans were designed to give a good turn of speed and do so with low horse power. To do that they need to be kept light thus only two stringers and no framing. They worked and worked well but builders were not happy with the speed and started putting way more power on them than Renn had intended. The result was a number of them cracked the stringers. As they say you can't fix stupid. :help:
Would you say the C series is a stronger design? 4 stringers. Sole not optional but structural?

Then add foam filled as well generally?

I guess any boat can break but I can’t help but feel that a designer selling plans must have in the back of his mind the need to put in a huge margin of safety because of the Cavalier attitude to just sticking bigger and bigger motors on the back...

Was Tolman as constrained by this? Did he sell plans or a How to Book? Does that change your liability as a designer?

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Nov 18, 2020 3:11 am
by cracked_ribs
Personally, I think the C series is a stronger design; I have never attempted the math on either design but just looking over both, I prefer the smaller unsupported park size of the C boats. The thicker ply on the Tolmans is a necessity, I think, because of the single stringer per side. The unsupported areas are necessarily larger. Plus the soles on the C boats as I think you noted is not optional but structural - that box is very strong.

Liability issues I don't know anything about, I just build boats, write stuff and design communication systems.

I'm not anti-tolman at all (I don't own Tolman plans but I do own Great Alaskan plans and I'd consider building one, for sure) but I think the C series is a step up from the Tolmans as designs go.

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Nov 18, 2020 11:52 am
by TomTom
Curious if most people brush or roller in their lockers?

This time around I don’t think I have the stamina to worry too much about the finish inside lockers ... but I feel that a bit of texture probably helps conceal all the defects?

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Nov 18, 2020 3:44 pm
by Fuzz
I don't think Renn was a trained navel engineer. He was just a pretty smart fellow who needed a boat to run around in that did not cost a ton to build or operate. He built a boat and it worked out so well others wanted one and the whole thing evolved. It is the wood in a tolman and not the glass that makes it strong. I know of one 26 footer being built that has two layers of 6 oz cloth on the outside. Not sure what the plan is for the inside as it was still upside down when I saw it.
In my mind the C series are much stiffer boats. They have more stringers and framing. But the Tolmans work and work well. I have seen a 20 foot Tolman with a cabin and three men in it push up on step with 40 hp. I was darn impressed.

Re: C19 Stretch and re-build Progress Report...

Posted: Thu Nov 19, 2020 2:51 am
by OneWayTraffic
If you deck a Tolman you could install all the frames. The larger boats have more stringers as well.

If you build a C series you can add glass or use 9mm ply.

But both boats are more than strong enough for the use so why bother.

I saw the main disadvantages of the Tolman the large amount of fitting from the boat (the side panels are not developed using CAD you need to plank scribe remove cut replank.) The use of imperial measures and the references to things I can’t get in NZ. It’s definitely a how to book with comprehensive notes. You can get a copy sent on Amazon for not that much $.

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Nov 23, 2020 12:38 am
by TomTom
Final topcoat of Jotun Hardtop white on the outside....

Image

Image

Image

Image

Re: C19 Stretch and re-build Progress Report...

Posted: Mon Nov 23, 2020 1:23 am
by cracked_ribs
Boy, you sure nailed the sheer line on that boat.

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Nov 24, 2020 11:24 am
by TomTom
cracked_ribs wrote: Mon Nov 23, 2020 1:23 am Boy, you sure nailed the sheer line on that boat.
Thanks - I am really enjoying watching your build. Pretty lines. Can’t wait to see how she turns out.

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Nov 24, 2020 5:09 pm
by Dan_Smullen
Dude. She is looking bad to the bone!

Re: C19 Stretch and re-build Progress Report...

Posted: Wed Nov 25, 2020 12:04 am
by cracked_ribs
TomTom wrote: Tue Nov 24, 2020 11:24 am
cracked_ribs wrote: Mon Nov 23, 2020 1:23 am Boy, you sure nailed the sheer line on that boat.
Thanks - I am really enjoying watching your build. Pretty lines. Can’t wait to see how she turns out.
Ah, thank you. It's a long way from finished of course but I'm really looking forward to seeing it flip myself.

Re: C19 Stretch and re-build Progress Report...

Posted: Thu Nov 26, 2020 11:02 am
by TomTom
Image

Image

Got the rod holders cut out and doing some finishing on the woodwork...

Re: C19 Stretch and re-build Progress Report...

Posted: Tue Dec 29, 2020 4:41 pm
by TomTom
A few more progress pics .... getting close now ....

Image

Image

Image

Image

Image

Re: C19 Stretch and re-build - nearly there!!

Posted: Sun Nov 21, 2021 12:57 pm
by TomTom
Some progress pics. All the paint/ clear coat has been done. Just putting all the fittings, rod holders etc in and wiring up the engine now...

Image

Image

Image

Image

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Nov 21, 2021 1:04 pm
by fallguy1000
Those gunwhales are beautiful. It must be very good feeling to be at this juncture after all the troubles.

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Nov 21, 2021 1:18 pm
by TomTom
fallguy1000 wrote: Sun Nov 21, 2021 1:04 pm Those gunwhales are beautiful. It must be very good feeling to be at this juncture after all the troubles.
Will feel better when I know she floats 😂😂

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Nov 21, 2021 1:27 pm
by fallguy1000
Didn't you have it in the water once already since the stretch?

Re: C19 Stretch and re-build Progress Report...

Posted: Sun Nov 21, 2021 1:37 pm
by TomTom
fallguy1000 wrote: Sun Nov 21, 2021 1:27 pm Didn't you have it in the water once already since the stretch?
Yeah - I did - to draw the waterline. I guess I meant I will feel better when I know she floats under power!

Re: C19 Stretch and re-build - getting close now ...

Posted: Mon Nov 22, 2021 12:16 pm
by cracked_ribs
This is one I'm really looking forward to seeing run again. I really like the slightly narrower shape of the stretched 19 vs the 21 and to fix that one up after the delamination nightmare...that's just a great outcome. Keep us posted!

Re: C19 Stretch and re-build - getting close now ...

Posted: Tue Nov 23, 2021 5:18 am
by cape man
The whole thing is awesome, but agree the gunwales are impressive, and the sheer is spot on. So happy to see you doing this.

Re: C19 Stretch and re-build - getting close now ...

Posted: Sun Nov 28, 2021 1:11 pm
by TomTom
A few more pics ...

Image

Image

Image

Re: C19 Stretch and re-build - a few more pics ...

Posted: Sun Nov 28, 2021 1:35 pm
by TomTom
Need to put engine on, do the wiring and the anti-foul and should be good to go!

Any suggestions for a good bow roller/ anchor system?

I am thinking of putting a small “sacrificial” pulpit ...

Re: C19 Stretch and re-build - getting close now ...

Posted: Sun Nov 28, 2021 1:42 pm
by Fuzz
That is one amazing transformation! You have done yourself proud :D

Re: C19 Stretch and re-build - a few more pics ...

Posted: Sun Nov 28, 2021 2:58 pm
by fallguy1000
TomTom wrote: Sun Nov 28, 2021 1:35 pm Need to put engine on, do the wiring and the anti-foul and should be good to go!

Any suggestions for a good bow roller/ anchor system?

I am thinking of putting a small “sacrificial” pulpit ...
I went to imtra's website and bought a clearance roller for 150 plus a delrin roller for 61$. Those are 316 stainless.

Re: C19 Stretch and re-build - a few more pics

Posted: Sun Nov 28, 2021 5:42 pm
by BarraMan
Well, if you're going to do it, you might as well make a job of it!
Beautiful boat - makes me feel a bit inadequate! :lol:

Re: C19 Stretch and re-build - a few more pics

Posted: Sun Nov 28, 2021 6:15 pm
by cape man
Can't wait to see that in the sun. Wow!

Re: C19 Stretch and re-build - a few more pics

Posted: Sun Nov 28, 2021 9:09 pm
by TomW1
TomTom that is one beautiful boat. Tom

Re: C19 Stretch and re-build - a few more pics

Posted: Mon Nov 29, 2021 5:00 am
by TomTom
Thank you all for the kind remarks. She is not without her imperfections. And truth be told building from scratch may well have been faster/ easier. But I have enjoyed the process and I am curious how differently she will behave with the added length. There is nothing for free in boating - that is for sure!

One day when this covid nonsense is behind us I would love to come to a bateau meet and take a ride in some of the other great designs I have scratched my head over all these years!

I still can’t help think that the PG 25 would have ticked all the boxes I was looking for in a boat.

Re: C19 Stretch and re-build - a few more pics

Posted: Mon Nov 29, 2021 8:32 am
by Jeff
Nice work!!! Jeff

Re: C19 Stretch and re-build - a few more pics

Posted: Tue Dec 07, 2021 10:29 am
by TomTom
Engine on now. Hoping to get it connected by end of the week. Need to replace the eyelets on the canvas for the T top and connect bilge pump and do some small wiring. Feels like we are on the final straight!

Image

Image

Image

Re: C19 Stretch and re-build - Engine on!

Posted: Tue Dec 07, 2021 12:16 pm
by cape man
Is that all mahogany?

Re: C19 Stretch and re-build - Engine on!

Posted: Tue Dec 07, 2021 1:38 pm
by TomTom
Image

Re: C19 Stretch and re-build - Engine on!

Posted: Tue Dec 07, 2021 1:42 pm
by TomTom
cape man wrote: Tue Dec 07, 2021 12:16 pm Is that all mahogany?
Yup

Re: C19 Stretch and re-build - Engine on!

Posted: Tue Dec 07, 2021 6:26 pm
by BarraMan
Excellent taste in outboards! :D

Re: C19 Stretch and re-build - Engine on!

Posted: Wed Dec 08, 2021 1:57 am
by TomTom
BarraMan wrote: Tue Dec 07, 2021 6:26 pm Excellent taste in outboards! :D
I had a FICHT Ram 90 HP on her before. Picked up 2 that were sitting in a store in a hotel that had run them for a while on their boats (in freshwater). The boat drivers had said they were awesome and quiet; burnt very little fuel but no one in the country could maintain them. They had less than 300 hrs and I got them both for 750 bucks. By subbing parts around I got the one working and then I bought the spares for the other and found some diagnostic software on eBay. But always had a love-hate relationship with that engine. I thought it was amazingly clever technology - but almost too clever for the “computing technology” that ran it. They were so sensitive to voltage changes. If we had had a dealer nearby I may have felt different - but when this yammi came up for sale on a friends ski boat I jumped at the chance. It’s got 99 hrs on it.

Re: C19 Stretch and re-build - Engine on!

Posted: Wed Dec 08, 2021 11:23 am
by cracked_ribs
That boat is looking fantastic - really stoked to see the successful rebuild and stretch. I think you and I have similarly busy schedules so I am not checking in here quite as often now but this is one I am really chafing at the bit to see performance reports on once it's back in service.

Your description of the Ficht motors is what I would call "classic Evinrude." I love Evinrude stuff...but it's often like that: too clever by half. I love the E-tecs too, but they're the same way. Moments of brilliance...incredible power...managing to make 2-strokes efficient...genius on top of genius and then: hey the computer is getting really hot, any downsides to running salt water through it to cool it down? Not a one, go for it. Hey, how about fuel injectors that can't tolerate the tiniest deviation from spec without causing massive problems...should we include those but make them super expensive and require factory programming to switch them on so replacing even one is a giant pain in the ass? Yes, let's definitely do that.

I genuinely regret the loss of Evinrude outboards on the market, but man, they were the kings of the flawed masterpiece.

Re: C19 Stretch and re-build - Engine on!

Posted: Wed Dec 08, 2021 11:29 am
by VT_Jeff
Agreed, CR. This was a truly inspiring project to follow: take a boat that you spent a few years building, which then had some very serious issues due to material problems, and instead of scrapping and starting fresh, you salvage, re-build, improve, refine and re-finish it into something better and beautiful. Hats off, amazing work!
cracked_ribs wrote: Wed Dec 08, 2021 11:23 am ...the kings of the flawed masterpiece.
This perfectly describes the exhaust system on my MB diesel sprinter.

Re: C19 Stretch and re-build - Engine on!

Posted: Wed Dec 08, 2021 2:38 pm
by TomTom
cracked_ribs wrote: Wed Dec 08, 2021 11:23 am That boat is looking fantastic - really stoked to see the successful rebuild and stretch. I think you and I have similarly busy schedules so I am not checking in here quite as often now but this is one I am really chafing at the bit to see performance reports on once it's back in service.

Your description of the Ficht motors is what I would call "classic Evinrude." I love Evinrude stuff...but it's often like that: too clever by half. I love the E-tecs too, but they're the same way. Moments of brilliance...incredible power...managing to make 2-strokes efficient...genius on top of genius and then: hey the computer is getting really hot, any downsides to running salt water through it to cool it down? Not a one, go for it. Hey, how about fuel injectors that can't tolerate the tiniest deviation from spec without causing massive problems...should we include those but make them super expensive and require factory programming to switch them on so replacing even one is a giant pain in the ass? Yes, let's definitely do that.

I genuinely regret the loss of Evinrude outboards on the market, but man, they were the kings of the flawed masterpiece.
Fingers crossed she performs as I hope she will!

Quite a relief not having to make sure the old Evinrude starts after 4 years! Your description makes me laugh.

It was when I had 18 different warning codes to deal with and changing the battery of the boat and adjusting the crank position sensor cleared them all that I realised there was way too much randomness going on in there for me to cope with!

The engine once lifted itself out of the water whilst ildling about 40 feet from a massive humpback whale that was rolling around with it’s fin towering above us … and I had no option but to switch the engine off! Naturally being an Evinrude disconnecting and reconnecting the battery seemed to reboot the whole thing and we had a good laugh and never understood why it did that until this day. Maybe the engine just had a sense of humour!

I greatly admire the technology- but as you say - it’s just too complicated for its own good!


Indexing spark plugs … so if you have a 4 cylinder engine you need at least 6 plugs just to make sure 4 are oriented correctly! 🤦‍♂️

Anyhoo…

Re: C19 Stretch and re-build - Engine on!

Posted: Wed Dec 08, 2021 5:33 pm
by cape man
I need pictures of it in the sun and on the water! You have done an amazing job.

Re: C19 Stretch and re-build - Engine on!

Posted: Thu Dec 09, 2021 12:39 am
by TomW1
Man TomTom what a great job. That Yamaha 150 should make her fly.

Tom

Re: C19 Stretch and re-build - Engine on!

Posted: Thu Dec 09, 2021 3:31 am
by TomTom
TomW1 wrote: Thu Dec 09, 2021 12:39 am Man TomTom what a great job. That Yamaha 150 should make her fly.

Tom
Do we get a speed “guesstimate” out of you Tom?!! I sadly have no idea what she weighs!

Re: C19 Stretch and re-build - Engine on!

Posted: Thu Dec 09, 2021 8:18 am
by Rmarsh
Amazing.!!!! You are a very talented man.

Re: C19 Stretch and re-build - Engine on!

Posted: Thu Dec 09, 2021 10:06 am
by TomTom
I am struggling to work out what gauge cable I need for a F150 4 stroke Yamaha - it’s about a 6 m run in each direction (conservatively) if I have the battery up under the console.

Should I be thinking of having a starter battery closer to the engine?

Re: C19 Stretch and re-build - Engine on!

Posted: Thu Dec 09, 2021 12:40 pm
by Jaysen
That would be ideal but likely impractical.

As to gauge, co sides going “up one” from recommendation of you can afford it. Ex: if math says 4 go 2. Thicker cables never hurt unless your chase tubes are too small or corner radius is to tight.

Re: C19 Stretch and re-build - Engine on!

Posted: Thu Dec 09, 2021 1:16 pm
by OneWayTraffic
https://drive.google.com/file/d/1nxgvP0 ... sp=sharing

Chapter 8.

the length given here is for each cable. It later states that you can add ~ 4m in total length to the cables. (2m for +ve and 2m for -ve.) AWG 2. If your model is more recent things might be different but not that different I would think. Of course a bigger wire would have less voltage drop.

I snipped a couple of the sections.

Re: C19 Stretch and re-build - Engine on!

Posted: Thu Dec 09, 2021 6:41 pm
by APLJaK
FWIW

In my CX19, I used 1/0 because I got a decent price on it. I placed both house and engine batteries under the passenger seat and ran the motor cable back to the port side, across in front of the motorwell and terminated in the starboard side compartment. The Yamaha (F115) engine cable then attach to a two post terminal block in this compartment. They are small - look to be about a #4-#6. 1/0 is definitely overkill. Somewhere I did the calculations and didn't need this heavy cable, but I figure this should be one less thing to worry about.

I also used the remaining 1/0 to feed the masterbus in my cuddy. This too is overkill, but I already had the cable. I also terminated here on a large 2 post terminal block and then stepped down with a smaller cable to feed my distribution panels. This cable was a bear to pull as I had a couple of sharp turns in the conduit. Cable lube is your friend!.

Hope this helps.

EDIT: ....AND I forgot to say. Wow, that thing is gorgeous. Nice job!

Re: C19 Stretch and re-build - Engine on!

Posted: Thu Dec 09, 2021 6:50 pm
by APLJaK
TomTom wrote: Thu Dec 09, 2021 3:31 am
TomW1 wrote: Thu Dec 09, 2021 12:39 am Man TomTom what a great job. That Yamaha 150 should make her fly.

Tom
Do we get a speed “guesstimate” out of you Tom?!! I sadly have no idea what she weighs!
If it helps, my CX19, with a Yamaha F115 sitting on a single axle EZLoader came in at 1500kg. I figure about 300kg for the trailer? So right around 1200kg for the boat (with cuddy) and motor (170kg). The boat had minimal fuel onboard when I weighed it (perhaps 50L = 36kg).

Re: C19 Stretch and re-build - Engine on!

Posted: Thu Dec 09, 2021 8:15 pm
by TomW1
TomTom wrote: Thu Dec 09, 2021 3:31 am
TomW1 wrote: Thu Dec 09, 2021 12:39 am Man TomTom what a great job. That Yamaha 150 should make her fly.

Tom
Do we get a speed “guesstimate” out of you Tom?!! I sadly have no idea what she weighs!

TomTom depending on load and fuel on board you should be able to reach mid to upper 40's. Again I used the C21's weights added some weight for all your beautiful wood and used my usual numbers for people, gear and supplies.

Tom

Re: C19 Stretch and re-build - Engine on!

Posted: Fri Dec 10, 2021 5:04 am
by TomTom
OneWayTraffic wrote: Thu Dec 09, 2021 1:16 pm https://drive.google.com/file/d/1nxgvP0 ... sp=sharing

Chapter 8.

the length given here is for each cable. It later states that you can add ~ 4m in total length to the cables. (2m for +ve and 2m for -ve.) AWG 2. If your model is more recent things might be different but not that different I would think. Of course a bigger wire would have less voltage drop.

I snipped a couple of the sections.
This is most useful! Thanks

Re: C19 Stretch and re-build - Engine on!

Posted: Fri Dec 10, 2021 5:05 am
by TomTom
TomW1 wrote: Thu Dec 09, 2021 8:15 pm
TomTom wrote: Thu Dec 09, 2021 3:31 am
TomW1 wrote: Thu Dec 09, 2021 12:39 am Man TomTom what a great job. That Yamaha 150 should make her fly.

Tom
Do we get a speed “guesstimate” out of you Tom?!! I sadly have no idea what she weighs!

TomTom depending on load and fuel on board you should be able to reach mid to upper 40's. Again I used the C21's weights added some weight for all your beautiful wood and used my usual numbers for people, gear and supplies.

Tom
I love your optimism! I doubt I would go that fast even if I could!

Re: C19 Stretch and re-build - Engine on!

Posted: Fri Dec 10, 2021 5:07 am
by TomTom
APLJaK wrote: Thu Dec 09, 2021 6:50 pm
TomTom wrote: Thu Dec 09, 2021 3:31 am
TomW1 wrote: Thu Dec 09, 2021 12:39 am Man TomTom what a great job. That Yamaha 150 should make her fly.

Tom
Do we get a speed “guesstimate” out of you Tom?!! I sadly have no idea what she weighs!
If it helps, my CX19, with a Yamaha F115 sitting on a single axle EZLoader came in at 1500kg. I figure about 300kg for the trailer? So right around 1200kg for the boat (with cuddy) and motor (170kg). The boat had minimal fuel onboard when I weighed it (perhaps 50L = 36kg).
Interesting. Somehow I am pretty good at making things too heavy - but she did seem to float quite light on her lines so I may be surprised!

Re: C19 Stretch and re-build - Engine on!

Posted: Fri Dec 10, 2021 5:08 am
by TomTom
Rmarsh wrote: Thu Dec 09, 2021 8:18 am Amazing.!!!! You are a very talented man.
I think most people would say pig-headed over talented! But thank you anyways!

Re: C19 Stretch and re-build - Engine on!

Posted: Fri Dec 10, 2021 5:12 am
by TomTom
Jaysen wrote: Thu Dec 09, 2021 12:40 pm That would be ideal but likely impractical.

As to gauge, co sides going “up one” from recommendation of you can afford it. Ex: if math says 4 go 2. Thicker cables never hurt unless your chase tubes are too small or corner radius is to tight.
Yes - I agree the heavier the better. Not worried about the chase tube as much as where it has to go into the engine through the rubber grommet alongside the rest of the wiring, the control cables and the fuel line. I have heard you can constrict the fuel here if you aren’t careful.

Re: C19 Stretch and re-build - Engine on!

Posted: Fri Dec 10, 2021 4:30 pm
by TomW1
TomTom wrote: Fri Dec 10, 2021 5:05 am
TomW1 wrote: Thu Dec 09, 2021 8:15 pm
TomTom wrote: Thu Dec 09, 2021 3:31 am

Do we get a speed “guesstimate” out of you Tom?!! I sadly have no idea what she weighs!

TomTom depending on load and fuel on board you should be able to reach mid to upper 40's. Again I used the C21's weights added some weight for all your beautiful wood and used my usual numbers for people, gear and supplies.

Tom
I love your optimism! I doubt I would go that fast even if I could!
Yep TomTom you don't need to run her at wide open throttle. Remember a C19 wiith a 115 runs 42 in real life, so your C21 with a 150 would not be unreasonable to reach my numbers. I think the mid 40's say 43-47 are very reasonable. It just depends on your load. I just don't know how much that extra wood added to the weight. Also the 150 weighs a little more than 100lbs over the 115. Good luck.

Tom

Re: C19 Stretch and re-build - Engine on!

Posted: Sat Jan 01, 2022 2:33 am
by TomTom
Image

Image

Launched yesterday! Still floating today. Hit 36 knots with 2 on board at 5400 rpm. Planing hump pretty much gone. 8 kts at 2100 rpm. Very pleased with the outcome.

Happy New Year everyone.

Re: C19 Stretch and re-build - Launched!!

Posted: Sat Jan 01, 2022 8:05 am
by cape man
Awesome!

Re: C19 Stretch and re-build - Launched!!

Posted: Sat Jan 01, 2022 11:50 am
by fallguy1000
Is there a pod for the engine or is that an illusion?

When you fish, do you troll? How fast?

Re: C19 Stretch and re-build - Launched!!

Posted: Sat Jan 01, 2022 3:21 pm
by TomTom
fallguy1000 wrote: Sat Jan 01, 2022 11:50 am Is there a pod for the engine or is that an illusion?

When you fish, do you troll? How fast?
No pod - I think you are seeing a white rope that makes it look like there is a break in the transom.

It is much wider than in the plans and has been modified though.

We troll for blue marlin with lures at 7-8 kts, sailfish at around 6 kts with lures/ strip bait and we live bait for wahoo, kingfish, black marlin at about 2-3 kts with small frigate mackerel or bonitos.

We also slow troll swimming dead baits for kingfish at less than 2 kts.

And slow troll strip bait in a lure with a glow stick at night for broadbill. You can also deep drop for them in the day.

Re: C19 Stretch and re-build - Launched!!

Posted: Sat Jan 01, 2022 10:38 pm
by Dan_Smullen
Sounds like great fishing. Good to see her back OTW!

Re: C19 Stretch and re-build - Launched!!

Posted: Sat Jan 01, 2022 11:51 pm
by TomTom
Image

Re: C19 Stretch and re-build - Launched!!

Posted: Sun Jan 02, 2022 12:12 am
by TomW1
She sure looks good TomTom. :D

Re: C19 Stretch and re-build - Launched!!

Posted: Sun Jan 02, 2022 10:33 am
by VT_Jeff
Looks awesome, congrats on a huge mission accomplished!

Re: C19 Stretch and re-build - Launched!!

Posted: Sun Jan 02, 2022 2:19 pm
by Fuzz
Very, very nice! Sounds like she is doing every thing you hoped for.

Re: C19 Stretch and re-build - Launched!!

Posted: Mon Jan 03, 2022 7:42 pm
by Dan_Smullen
A long sexy sled, for sure.

Regarding scupper tubes, are yours run similarly? About how high above the chine are yours?

Re: C19 Stretch and re-build - Launched!!

Posted: Mon Jan 03, 2022 10:41 pm
by TomTom
Dan_Smullen wrote: Mon Jan 03, 2022 7:42 pm A long sexy sled, for sure.

Regarding scupper tubes, are yours run similarly? About how high above the chine are yours?
These ones are just a hole through the transom. No tubes needed because I did away with a motorwell bulkhead that goes to the floor. I am currently making plugs for them. And considering elephant trunks or some sort of flap with a rubber band to keep them shut.

On my old version they were identical to yours in shape - and they passed through the side boxes to connect bulkhead to back of boat. My C19 may have been a bit heavy but they still sat a good 2 inches above the water and I ended up keeping them plugged when not on a mooring because we were forever having water round our feet and I got tired of fielding “are we sinking” questions!

My friend who built the GS28 has added those elephant trunks. He used to just plug and leave open on the mooring. But his new mooring (which is a bit more exposed) means water would come in when the front of the boat was lifted on a wave and then the little bit of water scooped in would go fwds as the wave passed the back of the boat and lifted the back - so essentially in the right conditions the rocking of the boat was a bit like a pump.

I personally think it’s very hard without some sort of plug/ flap system to not have some water come in sometimes on a small boat however high above the water the scuppers are.

Re: C19 Stretch and re-build - Launched!!

Posted: Tue Jan 04, 2022 7:16 am
by Jeff
Very nice!!!! Jeff

Re: C19 Stretch and re-build - Launched!!

Posted: Wed Jan 05, 2022 5:44 am
by TomTom
Some preliminary numbers … without taking current into account particularly

5/6kts @ 1700
6kts @ 1800
7kts @2100
8kts @2300
9kts@ 2500

Re: C19 Stretch and re-build - Launched!!

Posted: Thu Jan 06, 2022 3:43 pm
by APLJaK
She looks beautiful. Congratulations.

Re: C19 Stretch and re-build - Launched!!

Posted: Sat Jan 08, 2022 11:41 pm
by TomTom
Image

Testing how she corners at speed. I added a small skeg. I feel like it has made a huge difference to the steering and handling. It’s much easier to manoeuvre at low speed - and no tripping at high speed either.

Re: C19 Stretch and re-build - Launched!!

Posted: Sun Jan 09, 2022 10:50 am
by pee wee
TomTom wrote: Sat Jan 08, 2022 11:41 pm [bbvideo]https://i.imgur.com/snGVhOo.mp4[/bbvideo]

Testing how she corners at speed. I added a small skeg. I feel like it has made a huge difference to the steering and handling. It’s much easier to manoeuvre at low speed - and no tripping at high speed either.
That makes me dizzy!

Re: C19 Stretch and re-build - Launched!!

Posted: Sun Jan 09, 2022 1:05 pm
by Fuzz
Great video! Thanks for posting it.

Re: C19 Stretch and re-build - Launched!!

Posted: Sun Jan 09, 2022 7:41 pm
by TomW1
Looks great TomTom what speed were you at?

Tom

Re: C19 Stretch and re-build - Launched!!

Posted: Mon Jan 10, 2022 4:20 am
by TomTom
TomW1 wrote: Sun Jan 09, 2022 7:41 pm Looks great TomTom what speed were you at?

Tom
Not far off 40 mph going into the turn, obviously it then bled off. I am definitely a fan of a small skeg now.

Another interesting thing is that at 2000 rpm I get 6.7 kts with a friend standing behind the console - but if they move fwds it picks up to 7.4 kts. Quite a difference.

I have a place for a fuel tank in front of the console… I think that will help the balance at trolling speeds.

Re: C19 Stretch and re-build - Launched!!

Posted: Mon Jan 10, 2022 2:12 pm
by TomW1
Yep Tom the two tanks were part of the original design. Go for it. Just put a Y valve where you can reach it at the main fuel line so you can switch tanksi and keep fresh fuel in each.

Tom

Re: C19 Stretch and re-build - Launched!!

Posted: Wed Jan 12, 2022 12:49 pm
by TomTom
TomW1 wrote: Mon Jan 10, 2022 2:12 pm Yep Tom the two tanks were part of the original design. Go for it. Just put a Y valve where you can reach it at the main fuel line so you can switch tanksi and keep fresh fuel in each.

Tom
Might as well try and keep something original!!

Re: C19 Stretch and re-build - Launched!!

Posted: Mon Jan 17, 2022 5:16 am
by TomTom
TomW1 wrote: Sun Jan 09, 2022 7:41 pm Looks great TomTom what speed were you at?

Tom
TomW1 … a couple of questions … all I can find on the prop is 17- N … it is a stainless 3 blade. Does this mean anything?

Could the size numbers be hidden by the hub?

Now I am getting a max RPM of 5400 … on a 2012 Yamaha F150 BET … (it’s a digital tach).

Is this about right?

Should I consider lifting the engine a notch or two? There is no cavitation or slipping in turns.

This might take it above 5500 rpm which is the max operating range … but wondering whether it is worth playing with this and propellers. And how much difference this can have.

Would a 4 blade stainless for example be able to drop my trolling rpms and get me the same speeds at around 1500- 2200rpms?

Re: C19 Stretch and re-build - Launched!!

Posted: Mon Jan 17, 2022 3:50 pm
by TomW1
Hi Tom did some research on your Yamaha 2012 F150. Your prop pitch is to big if you are only getting 5400rpm's at wide open thottle. Max rpms for that motor per Yamaha is between 5500 and 6000rpm's for best top speed and longevity of the motor. The 5400rpms you mention is below the operating at max rpm and you need to reduce the prop diameter. As for the prop do you know who made it. The 17N stands for 17 New, what you don't have is diameter. It should be around 14 3/4-16" according to my prop catalogs for your motor. So, if you can find the diameter you will want to go down to a 15 pitch. You can measure the diameter also by taking a tape/ruler from the center to the furthest edge of one of the blades and multiply by 2.

As for lifting the motor if the large cavitation plate is within an 1" of the keel, don't bother with it right now. Let's worry about the prop for now.

Now as far as a 4 blade vs. a 3 blade I tend to recommend a 4 blade for people running offshore boats. A 4 blade helps make steering easier, maintains water contact better in rougher water and a couple of other reasons. But we need to know what 3 blade to fit on your boat before we can fit a 4 blade. Usually, I go down 2 pitches from a 3 blade for a 4 blade.

Well hope this helps. Let me know if you need anything else.

Tom

Re: C19 Stretch and re-build - Launched!!

Posted: Wed Jan 19, 2022 12:31 am
by TomTom
Hi TomW - my engine is a 2012 F150BET - I believe having looked it up that it’s max rpm is 5500 … so maybe I am closer than we thought?

Image

Re: C19 Stretch and re-build - Launched!!

Posted: Wed Jan 19, 2022 3:23 pm
by TomW1
Okay Tom the motor spec I got were for 5000-6000 and peak HP at 5500. But let's go with yours as they have made motors for other parts of the world before, I also just found the same specs today. So, in that case your prop needs no change. If you want to go to a 4blade drop to a 15 pitch if you can find the diameter, it should be on the barrel of the prop. Or if not get me the manufacturer and I can probably find it. They usually use one diameter with multiple pitch sizes. Or, if it is from a local shop you can take it to them and have them give you the diameter and recommend a 4Blade.

Let me know what you want to do on the 4Blade. Tom

Re: C19 Stretch and re-build - Launched!!

Posted: Thu Jan 20, 2022 11:41 am
by TomTom
TomW1 wrote: Wed Jan 19, 2022 3:23 pm Okay Tom the motor spec I got were for 5000-6000 and peak HP at 5500. But let's go with yours as they have made motors for other parts of the world before, I also just found the same specs today. So, in that case your prop needs no change. If you want to go to a 4blade drop to a 15 pitch if you can find the diameter, it should be on the barrel of the prop. Or if not get me the manufacturer and I can probably find it. They usually use one diameter with multiple pitch sizes. Or, if it is from a local shop you can take it to them and have them give you the diameter and recommend a 4Blade.

Let me know what you want to do on the 4Blade. Tom
Thanks Tom - what do I buy myself with a 4 blade?

Could I get lower RPMs at trolling speeds?

Could I get a faster top speed?

Ive heard certain propellers are better at keeping the nose down on a boat ... is this true?

Re: C19 Stretch and re-build - Launched!!

Posted: Thu Jan 20, 2022 10:54 pm
by TomW1
TomTom wrote: Thu Jan 20, 2022 11:41 am
TomW1 wrote: Wed Jan 19, 2022 3:23 pm Okay Tom the motor spec I got were for 5000-6000 and peak HP at 5500. But let's go with yours as they have made motors for other parts of the world before, I also just found the same specs today. So, in that case your prop needs no change. If you want to go to a 4blade drop to a 15 pitch if you can find the diameter, it should be on the barrel of the prop. Or if not get me the manufacturer and I can probably find it. They usually use one diameter with multiple pitch sizes. Or, if it is from a local shop you can take it to them and have them give you the diameter and recommend a 4Blade.

Let me know what you want to do on the 4Blade. Tom
Thanks Tom - what do I buy myself with a 4 blade?

Could I get lower RPMs at trolling speeds? A couple hundred.

Could I get a faster top speed? No top speed will decrease slightly.

Ive heard certain propellers are better at keeping the nose down on a boat ... is this true? Yes, read on, it depends on rake and cup.
You will lose 3-4 mph top end but gain an easier handling boat. Also, in rougher water it will help in steering and handling. This means keeping the nose down, but this depends on the rake of the prop. There are 4 parts of a prop diameter, pitch, rake and cup. The diameter and pitch set the basic size of the prop and speed of the boat. Rake and cup indicate how the prop will perform. Increasing rake or cup by too much will increase bow lift. Each increase the water held on the blade.

In conclusion a 4blade prop with low to moderate rake and cup is what you are looking for. In whatever diameter you find by 15 since we decided the 17 pitch was fine. Let me know what brands are available to you and I can help. Solas are available worldwide, I don't know what is available to you.

Let me know if I can help more. Tom

Re: C19 Stretch and re-build - Launched!!

Posted: Sun Jan 23, 2022 8:30 am
by TomTom
Hi TomW - many thanks. I will measure the diameter next time I am near the boat.

If my sole intention was to be able to troll at the lowest possible rpms would a 4 blade still be the way to go and do you think I could shave some rpms off my 2000 rpm/ 7kt speed?

Re: C19 Stretch and re-build - Launched!!

Posted: Sun Jan 23, 2022 11:54 am
by TomW1
Tom, I would say yes as the 4blade grabs more water, you should be able to get down to 800-1000 rpms. This should give you 3-5 mph.

Regards, Tom

Re: C19 Stretch and re-build - Launched!!

Posted: Tue Jan 25, 2022 1:49 pm
by TomTom
TomW1 wrote: Sun Jan 23, 2022 11:54 am Tom, I would say yes as the 4blade grabs more water, you should be able to get down to 800-1000 rpms. This should give you 3-5 mph.

Regards, Tom
I have measured the diameter and it is 13.3/4 inches with 17-N on it….

Re: C19 Stretch and re-build - Launched!!

Posted: Tue Jan 25, 2022 3:23 pm
by TomTom
TomTom wrote: Tue Jan 25, 2022 1:49 pm
TomW1 wrote: Sun Jan 23, 2022 11:54 am Tom, I would say yes as the 4blade grabs more water, you should be able to get down to 800-1000 rpms. This should give you 3-5 mph.

Regards, Tom
I have measured the diameter and it is 13.3/4 inches with 17-N on it….
Also have some updated speeds … these are off the digital speedometer that works on a pitot tube/ water pressure…

5400 = 40 mph
4500=34 mph
3600 =25mph
3400 =23mph
3300=21mph
2800- 15 mph
2400 = 11-13 mph
2000- 2200 = 10 mph
1800 - 9mph

Re: C19 Stretch and re-build - Launched!!

Posted: Tue Jan 25, 2022 9:07 pm
by TomW1
TomTom wrote: Tue Jan 25, 2022 3:23 pm
TomTom wrote: Tue Jan 25, 2022 1:49 pm
TomW1 wrote: Sun Jan 23, 2022 11:54 am Tom, I would say yes as the 4blade grabs more water, you should be able to get down to 800-1000 rpms. This should give you 3-5 mph.

Regards, Tom
I have measured the diameter and it is 13.3/4 inches with 17-N on it….
Also have some updated speeds … these are off the digital speedometer that works on a pitot tube/ water pressure…

5400 = 40 mph
4500=34 mph
3600 =25mph
3400 =23mph
3300=21mph
2800- 15 mph
2400 = 11-13 mph
2000- 2200 = 10 mph
1800 - 9mph
Tom was that your top speed at maximum rpm? Did you have any rpm's left? Tom

Re: C19 Stretch and re-build - Launched!!

Posted: Wed Jan 26, 2022 1:53 am
by TomTom
If I trim up slightly I can pick up about 2 extra mph … I haven’t seen the rpm go above 5400.

Re: C19 Stretch and re-build - Launched!!

Posted: Sun Jan 30, 2022 5:19 am
by TomTom
Image

Got the outriggers mounted. Just need to add a center rigger.

Re: C19 Stretch and re-build - Launched!!

Posted: Mon Apr 18, 2022 8:26 am
by TomTom
Nice half a morning outing to fill up the freezer whilst the mahimahi are around. Good sized cool box is probably the next project. Boat going well. Was happy with the fuel economy. 20lts in 3 hrs trolling at 1900 rpm wasn’t bad.

Image

Re: C19 Stretch and re-build - Launched!!

Posted: Mon Apr 18, 2022 10:19 am
by fallguy1000
How are you catching those?

Re: C19 Stretch and re-build - Launched!!

Posted: Mon Apr 18, 2022 2:35 pm
by Dan_Smullen
Yes! Beautiful haul. Beautiful boat and beautiful weather! That a wahoo in the mix too?

Re: C19 Stretch and re-build - Launched!!

Posted: Tue Apr 19, 2022 12:41 am
by TomTom
fallguy1000 wrote: Mon Apr 18, 2022 10:19 am How are you catching those?
Trolling small sailfish lures with a strip bait. Picked up a few followers with a chunk.
Dan_Smullen wrote: Mon Apr 18, 2022 2:35 pm Yes! Beautiful haul. Beautiful boat and beautiful weather! That a wahoo in the mix too?


Yes - one lonely wahoo in the mix!

Re: C19 Stretch and re-build - Launched!!

Posted: Fri Apr 22, 2022 3:39 pm
by OneWayTraffic
I’ve built my cooler seat from polyurethane foam sheets glued to plywood. I used a denser foam (100kg per cubic metre or 6lb per cubic foot). Since it’s a heavy foam I just glassed the inside with double bias and faired. Taped the inside corners with woven. It seems stronger than commercial coolers.

Re: C19 Stretch and re-build - Launched!!

Posted: Thu Apr 28, 2022 1:37 am
by TomTom
OneWayTraffic wrote: Fri Apr 22, 2022 3:39 pm I’ve built my cooler seat from polyurethane foam sheets glued to plywood. I used a denser foam (100kg per cubic metre or 6lb per cubic foot). Since it’s a heavy foam I just glassed the inside with double bias and faired. Taped the inside corners with woven. It seems stronger than commercial coolers.
Thanks One Way - I was thinking along similar lines.