Page 1 of 1

Mark's C21

Posted: Thu Jul 30, 2015 10:40 am
by mmachonis
Jacque,

My name is Mark Machonis. We have spoken together on the phone several times. I hope you are feeling well.

I received my kit this week. I am about to get started. I have a few questions based on Reading Sam Devlin's book.

In his book, he indicates that he builds using a female jig with the boat right side up to start. He indicated that by doing so, you can keep your structure in proper alignment throughout the stitching/filleting process. Then set a few main permanent frames and longitudinal supports, then flip the boat and complete the exterior. I kind of agree with him. It seems to me that if the structure is upside down, there is no way, or it is more difficult to measure that the frames are in proper alignment with the hull. In addition, the frames can be fastened to the hull structure with temporary screws without damaging the completed exterior. Assuming a male jig is used, the exterior is completed first and then the boat is flipped so temporary frames set with screws would damage the completed outside. My thought, based on Mr Devlin's premise, is to make a cradle that keeps the water line level. Stitch the hull structure together, Fillet and Tape the inside of the hull using spreader bars and temporarily place frames to maintain the alignment in the cradle. Glass the inside. Set the longitudinal supports and frames on the interior and then flip the boat. Fillet, Glass and paint the exterior and flip it back over to finish the inside.

Am I overthinking this? Am I misunderstanding something? What are the advantages and disadvantages to using either method?

Mark

Re: Mark's C21

Posted: Thu Jul 30, 2015 11:11 am
by Fuzz
Hey Mark welcome to the group!
I have no experience with building your boat or one of the boats here built on a jig. I did build an OD-18 and here is what I have learned. The best way to get it done is to follow the plan that is laid out for you. Others have done it and it works. Other builders have their methods and I am sure they work for them but if you go your own way with one of the plans here I think you may be sailing off into uncharted waters. Sometimes that is a lot of fun and sometimes not so much :lol: Before building my dory I had built 4 other boats from 18 to 36 feet so I did have a little experience. I still found following the tried and true plan was the best way of doing things. Just my two cents worth.
Fuzz

Re: Mark's C21

Posted: Thu Jul 30, 2015 11:15 am
by mmachonis
Fuzz,

So how do you assure the alignment on the Male Jig? Devlin explains that once your boat is twisted, it can never be untwisted.

Mark

Re: Mark's C21

Posted: Thu Jul 30, 2015 11:17 am
by mmachonis
Fuzz,

By the way, thanks for the advice. I truly appreciate it! I am a sponge trying to absorb all the knowledge I can!

Mark

Re: Mark's C21

Posted: Thu Jul 30, 2015 1:07 pm
by Fuzz
Mark,
Like I said I have not built one of the plans from here that use the male jig. You will find plenty of boats built that way and many tips on how to keep them straight. Read the building tutorials and they explain it very well. I am sure one of the guys with much more knowledge will chime in also. What I do know is if you follow the plans and the advise you will receive here you will end up with a good boat. Devlin and others design good boats and their ways work but the plans here work also and they work best if followed.
I have built three male mold boats using C-Flex. It is a totally different method with different materials. They have survived 20 years of commercial fishing in Alaska so I have to say the method works also. As they say there are many different ways to skin a cat.
Keep asking questions you will get answers here.
Fuzz

Re: Mark's C21

Posted: Thu Jul 30, 2015 3:28 pm
by mmachonis
Jacque and Fuzz

I re-read the Self-Aligning Jig Tutorial and it makes more sense to me now. With the Stations Frames and longitudinal supports in place the alignment should be correct. Using the motorwell knees as the last station supports in the stern provides the correct transom angle.

I'm on board.

Mark

Re: Mark's C21

Posted: Thu Jul 30, 2015 3:49 pm
by mmachonis
Jacque and Fuzz,

The sentence below is from the Self-Aligning Jig Tutorial:

I hope that you saw on the plans that we measure from a specific mold face, forward or stern side. Align that face with the line, not the other one. Center the mold on the strongbacks.

What does "we measure from a specific mold face, forward or stern side" mean?

I realize that the mold needs to sit on one side of the line marked on the StrongBack. The origin is at the bow in your diagram. So when you say "stern side", I assume the the frame will be on the far side of the line from the origin toward the stern. Is this correct?

I just want to be clear.

Thanks.

Mark

Re: Mark's C21

Posted: Thu Jul 30, 2015 4:29 pm
by TomW1
Mark you are correct. When it shows to align at the stern side of the mold use the stern side. When it shows the forward side use the forward side. Some boat plans use all forward or all stern others mix them. There will be one diagram in the plans that shows how the molds line up.

Tom

Re: Mark's C21

Posted: Thu Jul 30, 2015 4:31 pm
by Fuzz
Mark,
I do not have a set of plans here at this time so I will try to go fro memory. I could be wrong so keep that in mind. There will be one mold and will be lets call it the master. All measurements will be taken from the face of it. This will be shown on the plans. I hope this makes sense to you. The plans show it pretty clearly.
Fuzz

Re: Mark's C21

Posted: Thu Jul 30, 2015 4:33 pm
by Fuzz
I just saw Tom's post and he is totally correct and said it better than me.
Fuzz

Re: Mark's C21

Posted: Fri Jul 31, 2015 6:58 pm
by Eric1
Hi Mark,

Just want to wish you well on your build! My shoulder finally quit hurting enough for me to get a little done today.
Pretty cool that there is another person building the same boat at the same time!!

Peace, Love and Happiness,

Eric

Re: Mark's C21

Posted: Mon Aug 10, 2015 11:09 am
by mmachonis
Jacque, Fuzz,

I have completed the base of my Jig and I am about to start adding the Stations to the jig. I can see on the plans how the Stations are marked toward the stern of the measurement indicator so I will place them accordingly. In the kit I have, the stations are made of a fibrous material. It does not seem like wood. I am building my boat outside will this effect the stations? I will be covering the project with a tarp/tent. When I join the two station pieces together, do I use any fiberglass cloth? Or do I coat the puzzle like joint with a mixture of epoxy resin and hardener only? And do I coat both sides, one side then the other in separate application?

Thanks.

Mark

Re: Mark's C21

Posted: Mon Aug 10, 2015 8:35 pm
by mmachonis
  • Code: Select all

    [quote="mmachonis"]Jacque, Fuzz,
    
    I have completed the base of my Jig and I am about to start adding the Stations to the jig.  I can see on the plans how the Stations are marked toward the stern of the measurement indicator so I will place them accordingly.  In the kit I have, the stations are made of a fibrous material.  It does not seem like wood.  I am building my boat outside will this effect the stations?  I will be covering the project with a tarp/tent.  When I join the two station pieces together, do I use any fiberglass cloth?  Or do I coat the puzzle like joint with a mixture of epoxy resin and hardener only? And do I coat both sides, one side then the other in separate application?
    
    Thanks.
    
    Mark[/quote]
Jacque,

My name is Mark Machonis. We have spoken together on the phone several times. I hope you are feeling well.

I received my kit this week. I am about to get started. I have a few questions based on Reading Sam Devlin's book.

In his book, he indicates that he builds using a female jig with the boat right side up to start. He indicated that by doing so, you can keep your structure in proper alignment throughout the stitching/filleting process. Then set a few main permanent frames and longitudinal supports, then flip the boat and complete the exterior. I kind of agree with him. It seems to me that if the structure is upside down, there is no way, or it is more difficult to measure that the frames are in proper alignment with the hull. In addition, the frames can be fastened to the hull structure with temporary screws without damaging the completed exterior. Assuming a male jig is used, the exterior is completed first and then the boat is flipped so temporary frames set with screws would damage the completed outside. My thought, based on Mr Devlin's premise, is to make a cradle that keeps the water line level. Stitch the hull structure together, Fillet and Tape the inside of the hull using spreader bars and temporarily place frames to maintain the alignment in the cradle. Glass the inside. Set the longitudinal supports and frames on the interior and then flip the boat. Fillet, Glass and paint the exterior and flip it back over to finish the inside.

Am I overthinking this? Am I misunderstanding something? What are the advantages and disadvantages to using either method?

Mark[/quote]

Re: Mark's C21

Posted: Mon Aug 17, 2015 12:30 pm
by mmachonis
I would like to post some photos. Do I have the rights to post images? If so, how do I do it?

Re: Mark's C21

Posted: Mon Aug 17, 2015 12:58 pm
by pee wee

Re: Mark's C21

Posted: Mon Aug 17, 2015 1:11 pm
by jacquesmm
At the top of my building notes, I mention the Devlin book as a reference but I also say that, if there is a conflict, you MUST follow my instructions, not Devlin.
The Devlin boats are hybrid between plywood on frame and stitch and glue, mine are composite boats. The Devlin boats rely more on the wood for strength, mine rely more on fiberglass.

In our assembly method, there are no temporary screws to damage the skin. Please see the pictures in the gallery: there must be close to 100 boats shown there built on a male jig.
The male jig is standard practice.

I use the basket mold method (female mold) for several of my sail boat designs but not for planing power boats. It is very difficult to obtain a straight running surface with the basket mold.
Thousands of my planing boat designs have been built on a male jig.

Why complicate?

PS: I was designing and building "stitch and glue" boats well before the 1st Devlin book was published.

Re: Mark's C21

Posted: Tue Aug 18, 2015 12:17 pm
by mmachonis
http://gallery.bateau2.com/albums/userp ... DECK_2.JPG

Jacques,

I am sorry. I do not mean to offend. I am just curious. I am on board and ready to start the journey. I have an area to build and the jig is ready to start adding stations. I will send more pictures once the stations are added.

As I see it there are two key points to adding the stations to the jig, horizontal placement and centered vertical placement. This placement is all based on the origin point in the center of the jig at the forward most point of the bow. The horizontal placement of the stations is based on the length distance from the origin point to the measured distance of that station per the plans. The vertical placement of the station is based on the height distance from the origin to the waterline of that station. If we want to be able to crawl under the jig, we should add an additional 6 inches. The first station to be set should be the one that has the greatest distance to the waterline. The remaining stations will stay level to the first stations waterline and as such lining up all the stations on the same level waterline. The result is that the height distance of each station is the same from the origin to the waterline. So if I were to put a level lengthwise on the keel of the boat it would be level sitting in the jig. Yet the sheer and chine will vary based on the shape of the station.

Does that make sense? Is there anything I'm missing before I get started?

Thanks.

Mark

Re: Mark's C21

Posted: Tue Aug 18, 2015 1:10 pm
by jacquesmm
I am not offended, I was afraid . . .

For a pictorial explanation of the jig set up, see this tutorial;
http://www.bateau2.com/howto/jig.php

At some point in that tutorial, I mention offsetting the stringer layers: disregard that, we don;t do it anymore but everything else is correct.
You can't go wrong with your kit: the spacing of all the parts is set by the notches in the stringers and molds.
There is nothing to measure. You can not make a mistake: notches would not fit.

The only part where a builder can introduce an error is by not having the the molds plumb. They must be vertical.
One could also twist the whole thing but that would become evident as soon as you try to install a hull panel.

Re: Mark's C21

Posted: Tue Aug 18, 2015 1:52 pm
by jacquesmm
BTW, did you get the kit notes? It's a PDF file.
From your questions, it sounds like you don;t have them.
The molds are clearly marked with the BL (baseline).
There is almost nothing to measure but if you don't have the notes you may not know that the baseline is marked with little holes.

Re: Mark's C21

Posted: Tue Aug 18, 2015 3:50 pm
by mmachonis
If the kit notes came with the kit, I do not think I have them. Would you please send them to me as a pdf? Thanks.

Re: Mark's C21

Posted: Wed Aug 19, 2015 10:21 am
by mmachonis
Jacques,

I have a question about the transom epoxy setup. My C21 kit was cut to be a full transom. I see that I have three transom shaped pieces of plywood. I assume one is the Transom, the other is the Motorwell Bulkhead and the other would normally be the clamping board. Can I glue these three pieces together in any order or is there a particular piece that should be in the middle or on the outside/inside? I can't tell the difference between the three pieces. Also, when I glue them, should I glue two pieces together first and let that cure and then glue the third piece on to the other two. Should I screw them together to keep the pieces from moving while they cure? I seem to recall a post on Eric's C21 indicating that you do not need much weight on the piece while curing.

Are the motorwell sides different in my case with the full transom? The setup on the jig should still be the same, correct?

In addition, could you please let me know where I can get the Kit notes that you referred to in your previous post.

Thanks.

Mark

Re: Mark's C21

Posted: Wed Aug 19, 2015 10:53 am
by Cracker Larry
I don't know that boat specifically, but typically a transom is made of 2 or 3 identical pieces. If they are all the same size, then I would glue all 3 up together at the same time. Align them dry and drill 3 spaced holes through them to accept 1/4 or 3/8 wood dowels. These will maintain alignment of the panels. Take it apart. Give all 3 a pre-coat of epoxy on the glue sides. Apply glue to one with a notched spreader, insert dowel pins in holes, drop next panel on top, repeat for the next. It doesn't need much weight or pressure. A few concrete blocks, a piece of railroad track, a couple buckets full of water, something like that. No need for screws.

I'm sure Jacques will help with specifics.

Re: Mark's C21

Posted: Wed Aug 19, 2015 11:05 am
by jacquesmm
I will email the kit notes later today.
mmachonis wrote:Jacques,

I have a question about the transom epoxy setup. My C21 kit was cut to be a full transom. I see that I have three transom shaped pieces of plywood. I assume one is the Transom, the other is the Motorwell Bulkhead and the other would normally be the clamping board.
The transom is made from 3 layers. Those sheets are marked H14, H15 and H16. See the pencil marks in the lower right corner of each sheet. Those are 3 transom layers. let's not call them anything else.

The bulkhead in front of it is named H29 and is made from 10mm. It is also named F2 on the PDF files included in the kit notes.



Can I glue these three pieces together in any order or is there a particular piece that should be in the middle or on the outside/inside? I can't tell the difference between the three pieces.
There is no difference = there is no particular order.

Also, when I glue them, should I glue two pieces together first and let that cure and then glue the third piece on to the other two. Should I screw them together to keep the pieces from moving while they cure? I seem to recall a post on Eric's C21 indicating that you do not need much weight on the piece while curing.
That's up to you.
I would not screw and use moderate weight: good contact, no excessive pressure. Maybe 30 to 50 lbs spread all over (resin jugs?).


Are the motorwell sides different in my case with the full transom? The setup on the jig should still be the same, correct?
There is no motorwell, you have a full transom. There is a bulkhead (F2) in front of the transom. It is located by the notches in the stringers. And there are two longitudinal stiffeners between transom and F2. Those parts are named "transom braces" on sheet H21. You need the notes to see that.

In addition, could you please let me know where I can get the Kit notes that you referred to in your previous post.

Thanks.

Mark

Re: Mark's C21

Posted: Wed Aug 19, 2015 11:06 am
by jacquesmm
Thanks Larry for the detailed gluing instructions.
Dowels are better than screws.

Re: Mark's C21

Posted: Wed Aug 19, 2015 11:28 am
by mmachonis
Jacques,

One last question on the transom. I noticed Eric mention GelMagic when he was gluing his transom in Eric's C21 post on the forum. Do I use the Epoxy Resin and Hardener to glue the transom pieces together or do I use a specific SilverTip Epoxy Product (ie something with a special additive or for a specific purpose like the GelMagic) from the Epoxy kit? My understanding of the GelMagic is that it is used in places to prevent sagging. I will be gluing the transom on the floor so there is no chance of any sagging.

Thanks. Sorry for all the questions.

Mark

Re: Mark's C21

Posted: Wed Aug 19, 2015 12:55 pm
by jacquesmm
You ordered the Silver Tip and that includes GelMagic.
GelMagic is the epoxy glue that you use to glue transom, stringers, anything that needs gluing.

Re: Mark's C21

Posted: Wed Aug 19, 2015 1:51 pm
by jacquesmm
Did you receive the kit notes? It's a PDF file. I emailed it a few minutes ago.

Re: Mark's C21

Posted: Thu Aug 20, 2015 9:46 am
by mmachonis
Jacques,

Yes, I received the kit notes. Thank you, they are very helpful. I have an issue. My stongback base is only 24'' wide. In the kit notes you indicate the base should be 46.5''. The instructions on the Bateau website indicate the base should be from 24'' to 36''. Will I have a problem with a 24'' base?

Next, when gluing the planking puzzle joints, I assume I should be using the GelMagic for these also, is that correct or should I use the Epoxy Resin?

Next, the kit notes indicate that the molds should be epoxy glued together at the puzzle joint with a butt block optional. You had suggested to me to just take a piece of the MDF scrap and screw it on the seam to keep it together without any glue or epoxy. Can/Should I still follow the MDF scrap method without using glue or epoxy?

Next, when gluing the transom pieces together using the dowl method to keep their alignment, the dowl gets glued into the hole and becomes part of the transom, correct? So I will cut the dowl and sand it flush to the face of the transom, correct?

Thanks.

Mark

Thanks.

Mark

Re: Mark's C21

Posted: Thu Aug 20, 2015 10:30 am
by Cracker Larry
Next, when gluing the transom pieces together using the dowl method to keep their alignment, the dowl gets glued into the hole and becomes part of the transom, correct? So I will cut the dowl and sand it flush to the face of the transom, correct?
That is correct. Just leave them in there.

I've never used Gelmagic, or assembled a puzzle joint from a kit, but you never glue with epoxy alone. Either thicken it with wood flour, or use a product like Gelmagic.

Re: Mark's C21

Posted: Thu Aug 20, 2015 11:30 am
by jacquesmm
mmachonis wrote: Yes, I received the kit notes. Thank you, they are very helpful. I have an issue. My stongback base is only 24'' wide. In the kit notes you indicate the base should be 46.5''. The instructions on the Bateau website indicate the base should be from 24'' to 36''. Will I have a problem with a 24'' base?
It will work with a narrow base but there is a reason for the 46.5" width. It puts the vertical braces flush with the stringers, much easier.

Next, when gluing the planking puzzle joints, I assume I should be using the GelMagic for these also, is that correct or should I use the Epoxy Resin?
When you glue, you use GelMagic. However, you could skip the glue for the molds and use a butt block. I think i say that in the notes.
OK, let me decide: glue with GelMagic.

Next, the kit notes indicate that the molds should be epoxy glued together at the puzzle joint with a butt block optional. You had suggested to me to just take a piece of the MDF scrap and screw it on the seam to keep it together without any glue or epoxy. Can/Should I still follow the MDF scrap method without using glue or epoxy?

Next, when gluing the transom pieces together using the dowl method to keep their alignment, the dowl gets glued into the hole and becomes part of the transom, correct? So I will cut the dowl and sand it flush to the face of the transom, correct?
I don't use dowels but I agree that they will help, keep the layers from moving while the glue sets.
I don't care if you glue them or not but it makes sense to leave them in. It doesn't matter. Do what's easier.

Re: Mark's C21

Posted: Sun Aug 30, 2015 10:00 pm
by mmachonis
Jacques,

I am constructing my jig. I have all the stations setup except for the transom and station A. FYI - keep in mind I am building the full transom C21 kit. At what position across Station F2 do I place the Supports that determine the transom angle? I assume they should be flush with the bottom of the transom, but where along that plane? In addition, the angle on the supports appears different from the angle on the stringers. I don't understand why this would be, what am I missing?

Also, any suggestions for keeping the stations from moving as I align them plumb with the notches in the stringers. I feel like the whole structure moves as I try to adjust the bottom of the station frame to align to the stringer notch. So as I move the bottom, the top moves and I feel like I'm not getting anywhere.

On the same subject of plumbing the stations, I am measuring the distance between stations at the keel, the chine and the sheer to make sure they are the same at each, correct?

Thanks.

Mark

Re: Mark's C21

Posted: Mon Aug 31, 2015 9:18 am
by jacquesmm
mmachonis wrote:Jacques,

I am constructing my jig. I have all the stations setup except for the transom and station A. FYI - keep in mind I am building the full transom C21 kit. At what position across Station F2 do I place the Supports that determine the transom angle? I assume they should be flush with the bottom of the transom, but where along that plane? In addition, the angle on the supports appears different from the angle on the stringers. I don't understand why this would be, what am I missing?
The angle is the same.
For the location up and down: yes, flush with the bottom, with frame F2.
Lateral (distance from center), see the very first drawing in the kit building notes: flush with the stringers, on the inside face of the stringers. Clamp it or use screws.


Also, any suggestions for keeping the stations from moving as I align them plumb with the notches in the stringers. I feel like the whole structure moves as I try to adjust the bottom of the station frame to align to the stringer notch. So as I move the bottom, the top moves and I feel like I'm not getting anywhere.
Page 3 of the building notes shows drawings of 2x4's. Look at the gallery and do a search with the word "jig", you will see many pictures of the jig set up, same as my drawing. Do not worry about stability until all the parts are in place.
The stringer notches set the distance between molds, page one of the notes:
"Mark the strongbacks for the molds spacing. No need for extreme precision, the stringers will locate
the molds."
Once the bow mold and transom braces are in place, you will have some triangulation, it should not move anymore.


On the same subject of plumbing the stations, I am measuring the distance between stations at the keel, the chine and the sheer to make sure they are the same at each, correct?

Thanks.

Mark
Start with a level or if your strong backs are perfectly flat, a large square. The square can be a piece of plywood, a corner of a leftover sheet. Screw those corners to the strongbacks and mold uprights if you want.
Distances should be the same all along the molds but do not worry about 1/8". Give priority to the stringers nothces, not your measurements.
I give distances to help start the set up of the molds but you can build the whole jig without measuring anything: the stringer notches set the distances between molds.

Re: Mark's C21

Posted: Tue Sep 08, 2015 10:32 am
by mmachonis
Jacques,

I have completed my jig except for positioning the Transom. I have the transom set on the supports at the proper angle. My question now is where does the transom and the bottom of the hull intersect. The Transom is at an angle so it is not flush with the stringers or the supports at the very top of the transom as it sits on the jig upside down. Should the stingers intersect the Transom at the lower/near side edge of the transom or should the transom height be level with the stringers at the higher/far side edge of the transom?

Here are some pictures of the Jig so far:

http://gallery.bateau2.com/displayimage.php?pid=57415
http://gallery.bateau2.com/displayimage.php?pid=57413
http://gallery.bateau2.com/displayimage.php?pid=57416
http://gallery.bateau2.com/displayimage.php?pid=57417

As a final check before I start planking and stitching, I measured the distance between each station on each side of the boat at the chine and the sheer and tried to keep any difference within 1/2 inch ( you mentioned on the phone that the expert builders can keep the difference within 3/8 inch at best). Most were within 3/8. I think I had one station that was off by 1/2. In keeping this tolerance, the plumbness of the stations is slightly off. Is it common for this to occur? I know you mentioned measuring the diagonals between each station, but with the stingers in place, I can't run a straight tape from chine to chine. In addition, my strongbacks are in the way of measuring the diagonal from sheer to sheer. Can simply pick two opposite points on each station and measure those diagonals and achieve the same result as measuring the diagonals from sheer to sheer and from chine to chine? I also ran a string down the keel of the boat to see that all the centers of all the station frames lined up. I may have had one or two that were off by an 1/8 or less. Any other recommendations for verifying the positioning of the frames on the jig?

Thanks.

Mark

Re: Mark's C21

Posted: Tue Sep 08, 2015 12:23 pm
by jacquesmm
Image

The transom, stringer and transom brace bottom must be flush.


Image

Viewed from above, the transom brace butts against the stringer inside face.
That drawing shows your kit.

I'll reply to the distance question later but there is no need to measure, the spacing between molds is set by the notches.

Do not compare with the plans: the kit has extra molds and you have an extra bulkhead for the closed transom.

The pictures look good but I can't see the height of the transom.
It has all to be flush. Think of how the bottom panel will lay on it. The brace and the transom must touch the bottom panel.

Re: Mark's C21

Posted: Tue Sep 08, 2015 1:34 pm
by mmachonis
Jacques,

I wish my picture of the side view of the transom was a better picture. I took the picture before I had the question.

So if I understand you correctly, the highest point of the transom (meaning the lowest point of the transom, because the jig has the boat upside down) should be level with the highest point of the F2 Frame? This does not make them flush with the stringers on top, because the stringers sit in the groove cutouts and sit below the level of the highest point of the frame, in some cases. Is that correct?

Mark

Re: Mark's C21

Posted: Tue Sep 08, 2015 2:47 pm
by jacquesmm
Everything has to be in the same plane: the bottom surface.
Frames and stringers have to be set so that when you add the bottom, their edges just touch the bottom panel.
Same for the transom.
If necessary move things around a little bit. Check that your baseline is where it should be: there are marks drilled on the molds.

The notches have a tolerance of a little more than 1/8" to make assembly easier but I would not worry about 1/8".
That alignment would also result in a straight line along the keel.
Straight does not mean horizontal.

Re: Mark's C21

Posted: Wed Sep 09, 2015 6:49 am
by topwater
This pic mite help.
Image
Thats a 8' aluminum straight edge across the last bulkhead and transom . The outside
higher edge of transom is flush with everything.
Image
Hope this helped.

Re: Mark's C21

Posted: Wed Sep 09, 2015 8:27 am
by jacquesmm
Thank you. That pictures shows how it should line up.

Re: Mark's C21

Posted: Wed Sep 09, 2015 2:43 pm
by mmachonis
Thank you. That is exactly what I wanted to see.

Re: Mark's C21

Posted: Wed Sep 09, 2015 2:45 pm
by jacquesmm
That is what I tried to explain but a good picture is far better than a long discussion.
Thanks again Topwater.

Re: Mark's C21

Posted: Thu Sep 10, 2015 9:25 pm
by mmachonis
Jacques,

I just want to confirm that when gluing the planking puzzle pieces together, I use Gel Magic to glue them and I do not put any cloth or tape on the seam. Is that correct?

Mark

Re: Mark's C21

Posted: Fri Sep 11, 2015 9:08 am
by jacquesmm
Correct. The seams will be covered by glass later, when you fiberglass.

Re: Mark's C21

Posted: Mon Sep 14, 2015 10:47 am
by cazuza
What is better for the puzzle joints, GelMagic or epoxy?

Re: Mark's C21

Posted: Mon Sep 14, 2015 11:09 am
by jacquesmm
Doesn't matter as long as it fills the very small gap.

Re: Mark's C21

Posted: Wed Jul 06, 2016 10:16 am
by mmachonis
Jacques,

Its great to be back on the build! Remember me, Mark Machonis - C21 - Manahawkin NJ! I am about to start filleting the seams of my panels. I will attach a few pictures that will show the fairness of the boat right now before I start filleting just to make sure it appears fair enough for your standards. My question is this. I will be zip tying the bottom panels together at the keel and the lower side panel to the bottom panels at the chine per the instructions, but can fillet the bottom panels at the keel without having the bottom side panels attached to the bottom panels? Or does the weight of the bottom side panels help to keep the bottom panels in place? Just a thought, because it is easier to fillet the keel of the bottom side panels are not attached to the bottom panels.

Thanks.

Mark

Re: Mark's C21

Posted: Wed Jul 06, 2016 10:42 am
by Eric1
Hi Mark!
Glad to see you get back at your build!!! :)
I can't answer for Jacques but I waited until I had my side panels zip tied on. The weight seemed to help hold the bottom down.
I have posted a good many photos and I have tried to leave some detail in the comments. I hope they may be of some help.
Look for "Erics C21" in the gallery. Best wishes for a smooth build! 8)

Re: Mark's C21

Posted: Wed Jul 06, 2016 11:01 am
by jacquesmm
can fillet the bottom panels at the keel without having the bottom side panels attached to the bottom panels? Or does the weight of the bottom side panels help to keep the bottom panels in place?
I prefer not but you can do it if you pull the panels close to the frames, for example with straps.
Once that fillet and seam are built, the bottom panel will not bend anymore or barely.

Re: Mark's C21

Posted: Thu Jul 14, 2016 2:34 pm
by mmachonis
Jacques,

Good Afternoon!

I am verifying my frame alignment prior to attaching panels to the mold. I was wondering what the distance from the keel of frame B to the chine of the transom should be? Using the diagonals from the from the Keel of Frame B to the left and right Chine of the Transom to make sure they are the same. I am coming up with 174 inches.

I also plan to take a T-square and extend it level from the keel to the chine and measure the distance from the level edge of the square down to the edge of the chine and compare the distances for each side of each frame.

I was also considering putting equal sized spacer boards between each frame at the keel the chine and the sheer to assure a plum symetrical frame. The MDF Frames seems to bend a bit. It's not that much but enough to make me concerned about tolerances. The bend can be as much as 1/2 inch.

Is this over kill, or am I on the right track? Any suggestions?

Mark

Re: Mark's C21

Posted: Thu Jul 14, 2016 2:56 pm
by jacquesmm
That is a complicated request, I have to open the 3D model and calculate that but as you say, it is overkill.
We compare the diagonals to ensure squareness, it is a check. If your distances between frames are correct and the diagonals equal, you are fine.
If not, the panels will be too long on one side and too short on the other.

Re: Mark's C21

Posted: Thu Jul 14, 2016 7:35 pm
by mmachonis
I have done a dry run of attaching the panels to the boat and they fit fine from bow to stern. There is about a 1/8 - 1/4 inch pitch difference between the mounted transom and the cut angle of the sides of the panels as they meet the transom. There also appears to be a slight dip in the line of the keel as the bottom panels begin there sharpest bend to the bow. I need to test my theory with a straight edge or a level piece of string. However, I'm just checking to see if this is normal. I will send a picture if it turns out to be more than an optical illusion.

Re: Mark's C21

Posted: Fri Aug 19, 2016 10:34 am
by mmachonis
Jacques,

Good morning. I have a few questions. I hope you can help me. I have attached the bottom panels and lower side panels forming the keel, the chine and the lower bow. I have filleted the seams of the keel, the chine, the transom (from the keel to the top of the lower side panel) and the bow (to the top of the lower side panel) and am in the process of sanding them to get them ready for taping.

My question is when and how to attach the top side panels? I understand that it overlaps the lower side panel by 6 inches to create the style line. I assume I can tape the chine before I attach the upper side panel. However, it seems the upper side panel must be attached before I can begin to tape the keel, bow and transom in order to get a nice single tape line from start to finish. Also, how does the topside panel meet the transom being that there is an overlap of 6 inches between the lower side panel and the upper side panel? This is going to leave a 1/4 gap where the lower panel ends and the upper panel begins as they run up the side of the transom. I assume the gap is filled with ez-fillet, but I don't want to assume.

In addition, I have purchased the System Three Fiberglass Kit for the C21 in August of 2015 (last year). I have been working on the boat since then. I am taking my time going slowly on each step. My motivation is great so I am still excited as I progress on the boat, but I'm concerned that I may be going too slow where the shelf life of my resin kit will expire. Will the shelf life of these products expire anytime soon?

Thanks.

Mark

Re: Mark's C21

Posted: Fri Aug 19, 2016 11:30 am
by Cracker Larry
I'm concerned that I may be going too slow where the shelf life of my resin kit will expire. Will the shelf life of these products expire anytime soon?
I can answer that. No. Epoxy will last for years on the shelf. It's not like paint.
I assume the gap is filled with ez-fillet, but I don't want to assume.
That is a structural joint. It should be filled with epoxy and wood flour, or maybe gel-magic, not fillet material.

Re: Mark's C21

Posted: Fri Aug 19, 2016 3:20 pm
by mmachonis
Jacques,

I'm sorry to bother you again, but you did not answer my question regarding when and how to attach the upper panels to the lower panels. I know they overlap by 6 inches. My feeling is I need to get the bow seam filleted and sanded smooth on the lower panel prior to installing the upper panel. Is the upper panel glued with Gel-Magic like the stringers or should I use regular Epoxy Resin? Do I need to tape the bow seam on the lower panel before gluing the upper panel? If so, how many layers of tape. The lamination schedule says 2. Do I want two long unbroken layers of tape from the Transom Keel to the tip of the upper panel of the bow or should they be broken into parts?

Thanks.

Mark

Re: Mark's C21

Posted: Fri Aug 19, 2016 3:43 pm
by Jeff
Mark, I apologize but Jacques is away this weekend, until Sunday morning, on a cruise. I hope this does not delay you but that is exactly why you have not had a response as of yet. Sorry, Jeff

Re: Mark's C21

Posted: Fri Aug 19, 2016 4:07 pm
by Eric1
Mark, I had the same questions! Look at my thread "Eric's C21" it sounds like page three will be about where you are.
Here is a reply from page 5:
jacquesmm wrote:
Eric1 wrote:Jacques,

Just to make certain, I use the EZ Fillet to bond the bottom and side panels to the Transom, correct?
Yes, you build a fillet with the EZ Fillet and follow with fiberglass tape.

Also regarding the Transom bond, I zip tie these panels as tight as possible (flush)?
I screw the sides and bottom to the transom with temporary drywall screws but not too tight, I don't want a flat there. You can zip tie too then use EZ fillet to fill the gap.

I'm assuming I wait to fill the gap form by the transom and bottom panel.

I'm going back through my tie points and adding a small sectio of PVC pipe to keep the panels in position. That is a neat trick I saw on the forum.


Thank in advance,

Eric


I hope this helps you, have fun!

Re: Mark's C21

Posted: Fri Aug 19, 2016 4:42 pm
by mmachonis
Yes, Eric, it does help. Thanks. I'm following your lead. I've been reading your thread and trying to take in as much as I can from your build. Where are you from. I'm in New Jersey.

Re: Mark's C21

Posted: Fri Aug 19, 2016 9:40 pm
by Eric1
I'm from South Carolina.

Re: Mark's C21

Posted: Tue Aug 23, 2016 12:00 pm
by mmachonis
Jacques,

This is Mark Machonis, in New Jersey on my C21. I wanted to ask you how fit/attached the Upper Side Panels to the Low Side Panels. I know they over lap 6 inches to create the Style Line on the boat. How did you hold the panel in place after it was glued? I am using Gel Magic as my adhesive. I'm not sure what the best method is for holding the panel in place after it is glued. I will use screws on the transom. I'm not sure what to use on the bow and along the port and starboard sides, more screws, zip ties all the way through both panels?

Your help would be greatly appreciated.

I hope all is well!

Thanks.

Mark

Re: Mark's C21

Posted: Tue Aug 23, 2016 12:13 pm
by jacquesmm
I replied in the other thread.

Re: Mark's C21

Posted: Tue Aug 23, 2016 1:13 pm
by mmachonis
Jacques,

Good afternoon.

I saw the other thread from Eric. However, you only speak specifically to the attachment of the panels to the Transom. What about along the port and starboard sides and the bow? I will use the ez-fillet on the transom with screws to get the nice rounded edge for taping. I expect that the overlap of the two panels, upper and lower sides are glued together with Gel Magic like the stringers? How do I hold the panels together after they have been glued? If I am screwing them together, how do I get them nice and fair? I only have one shot to get this right. How is this generally done? How far apart do I put the screws? Do I need to put two rows of screws one upper by the style line and one lower near the inner style line (where the lower side panel ends on the inside of the boat.

I apologize, but I feel like I need more specifics, because I only have one shot to get this right.

Thank you.

Mark

Re: Mark's C21

Posted: Tue Aug 23, 2016 1:20 pm
by mmachonis
Jacques,

I just read the post on Eric's thread. Sorry for the confusion. So screws it is. Any particular pattern to keep it fair without any flats?

Mark

Re: Mark's C21

Posted: Thu Sep 08, 2016 10:29 am
by mmachonis
Jacques,

I have some pictures and a question:

http://gallery.bateau2.com/displayimage.php?pid=61727

http://gallery.bateau2.com/displayimage.php?pid=61728

http://gallery.bateau2.com/displayimage.php?pid=61729

http://gallery.bateau2.com/displayimage.php?pid=61730

There are two pictures of the transom where the top panel meets the transom. I took these pictures to show how my top panels did not end up being flush with the transom. When I dry fitted the panels to make them flush with the top of the transom and align/meet at the bow, the panel seems to not fit correctly. I'm sure it's me not the panels. The alignment of the transom looks accurate, but the top panel is about an inch short on the port side and an inch and a quarter short on the starboard side. the transom is only an inch and a half thick. Will this be OK when it is filleted and taped? That is ultimately my question. Can I continue or do I need to cut/grind out the transom to free it and realign it moving frames under the already glued bottom, lower side and top panels? Yikes!! My build has a Full Transom. The F-1 frame is 15 inches from the transom to provide additional support along with the stringers and sole etc that will connect directly to the transom.

I am in your hands. What is your advice?

Thanks.

Mark

Re: Mark's C21

Posted: Thu Sep 08, 2016 10:32 am
by mmachonis
Starborad Side of Transom and Top Panel Intersection:

TOP_PANEL_INSTALL_STARBOARD_SIDE_TRANSOM_JOINT.JPG

Port side of Transom and Top Panel Intersection:

TOP_PANEL_INSTALL_PORT_SIDE_TRANSOM_JOINT.JPG

Re: Mark's C21

Posted: Thu Sep 08, 2016 10:37 am
by Marshall Moser
Image

Image

Image

Image

Re: Mark's C21

Posted: Thu Sep 08, 2016 10:42 am
by jacquesmm
That upper panel should have been aligned starting at the transom. No big problem, epoxy will weld all that together but the idea is to have a nice radius on the upper panel at the bow, not a sharp end.
It is really minor, nothing to worry about.
Besides that, it looks really good.

Re: Mark's C21

Posted: Mon Sep 19, 2016 10:08 am
by mmachonis
Jacques,

Good morning. Well I am almost ready to begin Taping. I was wondering how to prevent wrinkles in the Tape on the bends in the boat, especially at the bow? Do I need to make cuts in the sides of the tape at the bends and overlap them? If so, do I cut the tape all the way through and use several different pieces or do I use one long piece from the bottom of the transom to the top of the bow, cutting slices in the tape at the bends and overlaping them to make it lay flat on the boat surface?

By the way, I have never used fiberglass tape before. Any tips you can give me would be greatly appreciated.

Thanks.

Mark

Re: Mark's C21

Posted: Mon Sep 19, 2016 10:14 am
by mmachonis
Jacques,

I have another Taping question. Where the lower side panel and the upper side panel overlap and meet the transom (6 inch overlap), should I blend that all together with EZ fillet for the width of the Tape so the Tape will lay flat or should I maintain the two different levels created by the panels overlaping?

Thanks.

Mark

Re: Mark's C21

Posted: Mon Sep 19, 2016 10:48 am
by Eric1
mmachonis wrote:Jacques,

Good morning. Well I am almost ready to begin Taping. I was wondering how to prevent wrinkles in the Tape on the bends in the boat, especially at the bow? Do I need to make cuts in the sides of the tape at the bends and overlap them? If so, do I cut the tape all the way through and use several different pieces or do I use one long piece from the bottom of the transom to the top of the bow, cutting slices in the tape at the bends and overlaping them to make it lay flat on the boat surface?

By the way, I have never used fiberglass tape before. Any tips you can give me would be greatly appreciated.

Thanks.

Mark

Hi Mark,

I used one long piece for the job. The tape will conform to the bends. Just lay it down and run your hand over it and it will take the form.

mmachonis wrote:Jacques,

I have another Taping question. Where the lower side panel and the upper side panel overlap and meet the transom (6 inch overlap), should I blend that all together with EZ fillet for the width of the Tape so the Tape will lay flat or should I maintain the two different levels created by the panels overlaping?

Thanks.

Mark
I did fill this space with EZ Fillet to make the tape form without air gaps, both at transom and bow. The transom was the only place that gave me issue with the biaxial tape.
Jacques sorry for jumping in if this is not what you want done. This was just my experience.

Re: Mark's C21

Posted: Mon Oct 03, 2016 10:59 am
by mmachonis
Jacques,

Hello, I know you are busy so I will be succinct. I am about to start taping, any suggestions on where to start taping first? I was thinking the Chine, then the Bow/Keel. The Chine gets one layer of tape on the outside. It will be covered by the spray rail/chine log and a layer of epoxy for leveling the bottom of the boat to the spray rail/chine log which then transitions to the lower side panel above the spray rail/chine log. The Keel and the Bow get two overlapped layers of Tape on the outside. Do I put one layer of tape on at a time or both layers at the same time. I assume it will be both layers at the same time, is this correct? Then I will Tape the Transom with two overlapped layers on the outside. The Two layers will be applied at the same time, correct? When taping the Transom, how do I maintain the style line on the side? The angle of the overlap of the bottom side panel and the top side panel does not have 1/2 inch radius, any suggestions? I was considering putting a sloping 4inch layer of fillet to smooth out the style line at the Transom to allow the tape to be applied evenly with out any extreme bends, what do you think? I looked at Stefan's online and his looks like he maintained the style line all the way to the transom without making any adjustments to smooth out the style line at the transom. I also assume that the transom tape will overlap the Keel and Chine Tape, correct? The Chine Tape will be overlapped by the Keel/Bow Tape, correct?

Thanks.

Mark

Good luck at the show!!

Re: Mark's C21

Posted: Mon Oct 03, 2016 11:56 am
by mmachonis
Jacques,

One more question. The 6 inch wide tape is for what and the 4 inch wide tape is for what? The 4 inch wide tape is a very fine weave. The 6 inch tape is a much more course weave.

Thanks.

Mark

Re: Mark's C21

Posted: Mon Oct 03, 2016 12:15 pm
by bateau-webmaster
Biax (12oz coarse knit) is for all seams, woven (6 oz 4") is for the console I believe.

Re: Mark's C21

Posted: Mon Oct 03, 2016 12:36 pm
by mmachonis
There was another post today before the most recent one you answered, can you answer that one too.

Re: Mark's C21

Posted: Mon Oct 03, 2016 12:45 pm
by bateau-webmaster
I had a whole big reply for the previous post here, and somehow lost it. I thought I submitted it, but . . .

I would tape the keel line first, then the chines, so you don't have to reach over wet epoxy.

Lay out one layer at a time where there is an overlap, but you can begin laying out the next layer once the first one is wet out. It may help to let it tack up just a little, as it will hold the tape in place better.
same with the transom, though here you have to worry more about the angle, as it is vertical, make sure the first layer is nice and tacked up before you put the second on, possibly mostly hardened, otherwise you run the risk of it sliding off with two layers on a vertical surface.

for the style line: fillet putty under the tape will help it hold its shape to the style line, you might press it into the crease with a spreader once everything is wet out, so that the tape stretches a bit, but is held in place to the surface.

as far as keeping the line with the tape, the wide cloth should help to smooth out the difference, and fairing will fill in the rest.

Transom tape overlaps longitudinal tape lines, yes. the lines at the bow depend on the order you lay them out.

Re: Mark's C21

Posted: Tue Oct 04, 2016 8:40 am
by Jeff
Mark, did we get the response to you early enough yesterday to get the work accomplished? Jeff

Re: Mark's C21

Posted: Tue Oct 04, 2016 11:40 am
by mmachonis
Yes, thank you Jeff.

Re: Mark's C21

Posted: Tue Oct 04, 2016 3:37 pm
by Jeff
Sorry that we were away and not immediately available but glad in the end we were able to help!! Send us some photos!! Jeff

Re: Mark's C21

Posted: Tue Oct 04, 2016 7:02 pm
by jacquesmm
Mark, sorry for the delayed reply but I had not internet access since Friday.

What Jamie wrote is essentially correct.

For the lamination sequence, there is a drawing included in the plans, titled "lamination schedule" and it shows the fiberglass application step by step. Th exact sequence does not really matter but it is easier to do it that way: taping first then follow with the wide fabric.
Always apply on rounded corner: grind and apply some putty if needed. The exact radius does not matter, the goal is to apply the glass without any air bubbles and in general, that means 1/2" or larger.

For the style line: I do not specify glass all the way up the sides. It is not necessary but many like to do it.
In that case, either you use the technique Jamie described or, you glass all the way to the style line, go over a little bit (1/2"?) and when the resin is "green", cut with a razor blade along the style line.
Green means hard cheese consistency. Do that once for the lower panel and once for the upper panel.
That gives you a sharp style line which I find aesthetically more pleasing.
Again, I don't glass above the style line.

In the coming days, replies will be slow: we have a hurricane coming and will be without power or internet.

Re: Mark's C21

Posted: Wed Oct 05, 2016 12:15 pm
by mmachonis
Jacques,

Thanks for your response. Be safe!

I have read the lamination schedule to which you are referring. Yesterday, I applied one layer of the 6 Oz Tape to the Chine per the lamination schedule. The result seems to be good. However, I need some direction for future reference.

1. What is the formula for applying tape? How much resin per length of tape, approximately? I remember the lamination schedule mentioning something about 50%, but I don't remember 50% of what, the total weight of the resin and the tape combined or 50% of the weight of the tape. This would be helpful to know for pre-measuring batches of resin and hardener. I would also like to know because I do not want to add any unnecessary weight to the boat.

2. The mixed resin has a thin viscosity. When I applied it to side panel at the chine, it ran quite a bit. Is there a way to optimize the epoxy use in these situations?

3. With the thin epoxy on the side panel, the result, when dried, leaves a very rough surface. The top side of the chine (The bottom of the boat in reality. However, the boat is upside down on the mold) received the resin nicely on the tape. However, the side panel at the chine has the design of the fiberglass tape fabric embedded in it. It is completely wetted out, but it is not smooth. When the fiberglass fabric is so close to the surface of the resin, how do I sand this and how much do I sand this? I can't imagine that I can sand this smooth? Do I need to fill these gaps with Gel Magic to make it smooth?

4. Also, along those same lines, there are a lot of imperfections in and around the tape. Do I need to sand the high spots and fill the low spots before applying the fiberglass cloth over the entire boat? What would I use to fill low spots, epoxy on the flat spots and Gel Magic on anything that is not flat like the Side Panels?

Thanks.

Mark

Re: Mark's C21

Posted: Wed Oct 05, 2016 6:10 pm
by jacquesmm
Sorry, I am at home preparing for the storm.

The tape we use on the C21 is 12 oz. but 6" wide. If you bought a kit, you got 12 oz. tape.

I can't really describe how to apply the tape, it is simple, I never thought of it, just did it.
I wet the ply where it goes, push the tape on it, add more resin and after a few minutes, the tape gets wet.
Here is a video showing the procedure;
https://www.youtube.com/watch?v=x6BIr0Kq0Bs

There must many other good ways to do it: I like to use a squeegee for the resin, many other like a brush or a roller. Try and see what you prefer.
The goal is to have all the fibers wet but no excessive amount of resin.

More later: that hurricane is getting close and I have to go on the roof to put the solar heater down.

Re: Mark's C21

Posted: Mon Oct 17, 2016 10:23 am
by mmachonis
Jacques,



I hope you weathered the storm without too much damage.

I have finished taping and I am concerned I have some air pockets on the seam in a few spots. Is there any thing I can do about them? I have some photos for you to look at.

]http://gallery.bateau2.com/displayimage.php?pid=62526

http://gallery.bateau2.com/displayimage.php?pid=62525

http://gallery.bateau2.com/displayimage.php?pid=62527

http://gallery.bateau2.com/displayimage.php?pid=62529

http://gallery.bateau2.com/displayimage.php?pid=62531

http://gallery.bateau2.com/displayimage.php?pid=62530

Thanks.

Mark

Re: Mark's C21

Posted: Mon Oct 17, 2016 10:24 am
by mmachonis

Re: Mark's C21

Posted: Mon Oct 17, 2016 12:03 pm
by bateau-webmaster
Issue discussed over the phone. The solution for those not privy to the phone call, is to simply slice the glass that did not adhere off, prep for next layer as necessary, fill the void with thickened epoxy, or e-z fillet, and glass the next layer. If you work wet on wet you can avoid sanding the dollop used to fill the void, by simply placing it, and glassing directly over the thickened epoxy, which will smooth it out.

Re: Mark's C21

Posted: Wed Oct 26, 2016 2:28 pm
by mmachonis
Jacques,

Good afternoon, I have almost finished taping and I am getting ready to lay the fabric over the hull of the boat. I just want to make clear what I need to do.

Any prep work necessary(?):

I have feathered the tape edge flush to the wood panel. I have sanded all the panels smooth where there were any drips or rough spots. I will clean the dust and wiped down the entire hull with acetone prior to glassing.

Layup of fiberglass pieces:

1. One piece of fiberglass cloth from transom to bow, from keel to chine overlapping six inches on all sides. (one piece for port side and one piece for starboard side). Lay it wet on wet, if possible.
2. One piece of fiberglass cloth from transom to bow, from chine to style line overlapping 6 inches at the chine. (one piece for port side and one piece for starboard side) Lay it wet on wet, if possible.
3. One piece of fiberglass cloth form transom to bow and from style line to sheer. Lay wet on wet, if possible.

Theoretically, I can lay the first layer at one time, (all six pieces at one time wet on wet), correct?

My question is, the piece of fiberglass cloth from the style line to the sheer from transom to bow, do I overlap anywhere, and if so where, at the style line?

All in all, 6 pieces of fiberglass cloth per layer of fabric overlapping six inches at each seam. (two layers of 6 pieces for a total of twelve pieces), correct?

Thanks.

Mark

Re: Mark's C21

Posted: Sat Oct 29, 2016 12:19 pm
by Eric1
Hi Mark,

I took this picture for you this morning. This is what the edge of my style line looks like so far. You can see that some epoxy is building at the end grain as I fair and sand. I hope this helps. I think it will be easy to tape the edge of the bottom panel and pull a fillet to get a nice internal radius here. At least that's my plan. :lol:

Image

Re: Mark's C21

Posted: Tue Nov 08, 2016 9:33 am
by mmachonis

Re: Mark's C21

Posted: Tue Nov 08, 2016 10:00 am
by Marshall Moser
Image
Image
Image
Image

Re: Mark's C21

Posted: Fri Sep 21, 2018 2:32 pm
by mmachonis
Well hello everyone! I'm back at the boat again. It's been awhile. I have a new hip now and, I'm ready dive in. I had to take a year off.

I am putting on the second layer of fiberglass cloth on the outside of the hull. I have the two keel glass panels already laid up that run from the bow to the transom. I am about to put on the chine glass panels. However, when I put the first layer of glass on, I put the chine glass panel on and then put a layer of glass on the wood panel that creates the style line in the hull. I realize the the style line wood panel does not require glass, but I prefer to glass it, which leads me to my question. Rather then cut a chine panel and a style line panel and lay them up separately, couldn't I put an EZ-Fillet bead along the style line, making it a diagonal style line, and cut one glass panel to cover both the chine and the style line panel? It would then be one panel from Chine to Sheer. It would seem that, this will provide for a more encapsulated structure.

To be honest, it is quite a pain trying to keep the style line intact while laying up the panels with excess resin getting everywhere. I'm not the neatest worker.

Is there any problem with this for which I am not thinking far enough ahead to see?

Thanks.

Re: Mark's C21

Posted: Sat Sep 22, 2018 8:34 am
by pee wee
I don't see a problem with doing it that way, as long as the glass can make the bends without air pockets.

Re: Mark's C21

Posted: Sat Sep 22, 2018 7:01 pm
by mmachonis
Jacques could you comment on my post of September 21st. Iā€™m curious to hear your thoughts on my proposal. Thanks.

Re: Mark's C21

Posted: Tue Sep 25, 2018 9:30 am
by mmachonis
Jacques,

I am putting on the second layer of fiberglass cloth on the outside of the hull. I have the two keel glass panels already laid up that run from the bow to the transom. I am about to put on the chine glass panels. However, when I put the first layer of glass on, I put the chine glass panel on and then put a layer of glass on the wood panel that creates the style line in the hull. I realize the the style line wood panel does not require glass, but I prefer to glass it, which leads me to my question. Rather then cut a chine panel and a style line panel and lay them up separately, couldn't I put an EZ-Fillet bead along the style line, making it a diagonal style line, and cut one glass panel to cover both the chine and the style line panel? It would then be one panel from Chine to Sheer. It would seem that, this will provide for a more encapsulated structure.

To be honest, it is quite a pain trying to keep the style line intact while laying up the panels with excess resin getting everywhere. I'm not the neatest worker.

Is there any problem with this for which I am not thinking far enough ahead to see?

Thanks.
Top

Re: Mark's C21

Posted: Sun Sep 30, 2018 9:06 pm
by mmachonis
Jacques,

I am looking into material for my strakes, chine log and sheer clamp. I saw the preforms that are sold on your supplies website. They look like they might work nicely. What size and preform do you recommend for the C21 Strakes, Chine log and Sheer Clamp? I realize this is subject to preference, to some degree. I assume the the preform lengths need to be scarfed together to reach the required length.

For the Strakes, I would like to maximize lift and stability. My understanding based on reading your posts is the stability is maximized with strakes that create defined lines perpendicular to the water. Yet lift is created by separation through a portion of the strake getting as close to parallel to the water. In this case, I would want a strake that is wide for lift and somewhat high for stability, correct?

For the Chine Log, my understanding is the sharper the chine log, the less resistance on the water, helping to increase top end speed of the boat. Perhaps allowing for a slightly smaller HP engine and therefore less total weight. What preform would you suggest for this?

For the Sheer Clamp, I plan to have wide rounded sheer clamp with a rub rail attached. I think I could just go with a flat length of preform that I could glue on while the boat is upside down then glue a half round to it, once the boat is flipped. Do I need to create a template for cutting this or do the preforms bend and twist to the contour of the boat?

I am also interested in putting a keel fin on the bottom of the boat. I expect to be beaching the boat often and want to minimize sand/object abrasion on the bottom of the boat. Also, it could help in protecting the propeller. Is this appropriate or not. What do you think?

Also, when attaching and glassing these items to the boat, can I use the 4 oz glass or do I use the 12 oz glass? The reason I ask is because it is impossible to glass an acute angle. I would think the 4 oz glass allow for more acute angles than the 12 oz glass relatively speaking. What angle limit am I dealing with here for each type of glass? Do I still need glass on 1/2 inch round angle with the glass and then sharpen the angle with fillet?

Thank you very much for your help!!!

Mark

Re: Mark's C21

Posted: Mon Oct 01, 2018 4:15 pm
by jacquesmm
Mark, those questions come back so often that I wrote what we call a "sticky" announcement at the top of this forum.
I hope it answers your questions.

For the sheer clamp/rubrail etc. you have a pattern.
:doh:
It is the leftover plywood from you topside panel, the sheer edge.
Cut leftovers from there, 1.5 or 2" wide and it will fit and bend perfectly.

Re: Mark's C21

Posted: Fri Oct 05, 2018 1:03 pm
by mmachonis
Jacques,

I will have to take a look to see if I still have those remnants left to facilitate making the sheer clam template.

Another question, should if start faring the boat before I put on the Skeg, Strakes, Step Chine and sheer clamp?

Also, I would like to make a step chine that turns into a spray rail as it moves toward the bow. Do you have any suggestion for constructing this. Should I just lay out the chine log so it overlaps at the bottom of the boat and just fill the gap with ez-fillet so it becomes level to the overlap of the chine log/spray rail. Then sharpen the outer edge with ez-fillet. The Step would end up being parallel to the water? If you know what I mean? Or is there a better way to make it?

Thanks for the advice regarding the fiberglassing the Style line panel. I think that will work nicely.

Thanks.

Mark

Re: Mark's C21

Posted: Fri Oct 05, 2018 3:21 pm
by jacquesmm
mmachonis wrote: ā†‘Fri Oct 05, 2018 1:03 pm Jacques,

I will have to take a look to see if I still have those remnants left to facilitate making the sheer clam template.
The top of the side panel is the sheer line. That means you have a pattern, just cut slices.

Another question, should if start faring the boat before I put on the Skeg, Strakes, Step Chine and sheer clamp?
That is a matter of preference but yes. Those appendages are in the way when you fair. Check how Eric did his C21, he posted lots of pictures.

Also, I would like to make a step chine that turns into a spray rail as it moves toward the bow. Do you have any suggestion for constructing this. Should I just lay out the chine log so it overlaps at the bottom of the boat and just fill the gap with ez-fillet so it becomes level to the overlap of the chine log/spray rail. Then sharpen the outer edge with ez-fillet. The Step would end up being parallel to the water? If you know what I mean? Or is there a better way to make it?
Just add a chine step along the chine. You can bend a small one and if you want a wide one, laminate several layers. Just as for the sheer, you have a pattern: it is the plywood leftover from cutting the lower side panel, chine edge.
Build up several layers and fair with QuickFair.

Re: Mark's C21

Posted: Sat Oct 06, 2018 8:49 am
by pee wee
If you don't have the remnants from cutting the hull panels you can draw the hull panel (top) anew and use that for your pattern.

Re: Mark's C21

Posted: Mon Oct 08, 2018 8:56 pm
by mmachonis
Jacques,

So I laid up the Starboard Bottom Panel over the weekend. It appears I have had some wetting out issues on this panel and I am wondering to what extent I need to be concerned about these. If it appears these wetting out issues are potential structural issues, what do you recommend to do to fix each? I took some pictures. I included a broken broom in the picture to give the pictures some perspective. The broom is approximately 6 inches wide and 3 feet long.
The Boat
The Boat
The Boat
The Boat
Wetting Out Issues on the Bottom Starboard Panel Near Chine
Wetting Out Issues on the Bottom Starboard Panel Near Chine
Wetting Out Issues on the Bottom Starboard Panel Near Chine
Wetting Out Issues on the Bottom Starboard Panel Near Chine
Wetting Out Issues on the Bottom Starboard Panel Near Chine
Wetting Out Issues on the Bottom Starboard Panel Near Chine
Wetting Out Issues on the Bottom Starboard Panel Near Bow
Wetting Out Issues on the Bottom Starboard Panel Near Bow
Wetting Out Issues on the Bottom Starboard Panel Near Stern
Wetting Out Issues on the Bottom Starboard Panel Near Stern
Wetting Out Issues on the Bottom Starboard Panel Near Stern
Wetting Out Issues on the Bottom Starboard Panel Near Stern
Wetting Out Issues on the Bottom Starboard Panel Near Middle
Wetting Out Issues on the Bottom Starboard Panel Near Middle
Wetting Out Issues on the Bottom Starboard Panel Near Middle
Wetting Out Issues on the Bottom Starboard Panel Near Middle

Re: Mark's C21

Posted: Mon Oct 08, 2018 9:03 pm
by mmachonis
Continuing the wetting out issue, This issues are all on the same panel and none the spots in the pictures have air pockets. This is all in the fabric.

Re: Mark's C21

Posted: Mon Oct 08, 2018 10:35 pm
by mmachonis
Continuing the wetting out issue, this is the second layer of fiberglass.

Re: Mark's C21

Posted: Mon Oct 08, 2018 11:42 pm
by fallguy1000
Don't do that!

You gotta get the glass wetted man!

Now it will be hard to fix....

Everyone has wetout troubles of some kind, but leaving large areas go dry is far worse than overwetting or air pockets.

I would honestly try to cut the sections out asap, but they are probably too cured up by now.

So, hmmm.

About the only thing I might try is rewetting those areas as a test. You mighy need to use a hair dryer or a heat gun (danger!). And you might try to scarify the area with a knife first.

Next time you do it(hope not), try to cut it out before it has overnite or within 12 hours.

Sometimes; it might release.

Error tips to avoid this....

Use a pvc roller on a paint frame to move excess resin. It works great and you can reuse the pvc tube, but only wipe it with acetone; it'll melt in acetone bucket.

Never run short. Any doubt mix another batch.

Use a bubble buster roller.

Lighting can fool you. Be careful of poor lighting.

Let us know how you end up fixing it.

Worst case is to sand it off and lay another piece in; use a 2" minimum overlap of the good section.

Sorry. Boatbuilding is rarely perfection.

Re: Mark's C21

Posted: Tue Oct 09, 2018 6:50 am
by thb
fallguy1000,

My natural reaction to his situation would be to add more epoxy on top of the weave which is a little dry. Why is this bad?? Won't the epoxy fill the weave and dry area?

You have a lot more fiberglass experience than me, but I have been fiber glassing for over 45 years.

Regards
Tom

Re: Mark's C21

Posted: Tue Oct 09, 2018 9:13 am
by mmachonis
Jacques, Guys,


Thanks guys for the responses. These areas were wet out thoroughly, but the fabric didn't take it in. I was sweating like a pig hanging over top of it on my scaffold. This is an outdoor build and it was pretty humid the day I was laying this up. I am using the System Three SilverTip Epoxy Resin. System Three indicates that humidity is not a factor with this resin and I must say this stuff is really good. Even in the humidity, the resin didn't blush. There was about 80% humidity that day. I think the fabric was contaminated by me. I live by the water and it is often humid. We don't get below 65% humidity often.

I assumed that I needed to fix this. All these spots are all on one panel. What I want to know is what is the best way to grind these places out? Sanding seems to slow or maybe the second step after some grinding. I would think grinding of some kind as a first step, but I don't know specifics. Can anyone tell me what tools and accessories would help facilitate this job.

I am also concerned about grinding back down to the wood on the chine seam or any other seam. The seams have fabric and tape over them. If I grind and sand down to the wood, do I build it back up with tape and fabric or just fabric or just EZ-Fillet? Any thoughts?

Once I get it ground down and sanded, I will brush a layer of epoxy on the spots to make sure they wet out below. Then I will use either fabric, tape or EZ-Fillet to fill the spots, depending on the size of the area. I want to do it right. Time is not a factor. I am not in any hurry.

I guess the lesson learned is conditions must be right for laying up fiberglass. I tested the limits and got bit. The next lesson will be how to fix areas that do not wet out properly and cure. If it happens again, I will cut out the spots before it cures.

Thanks.

Mark

Re: Mark's C21

Posted: Tue Oct 09, 2018 9:38 am
by fallguy1000
thb wrote: ā†‘Tue Oct 09, 2018 6:50 am fallguy1000,

My natural reaction to his situation would be to add more epoxy on top of the weave which is a little dry. Why is this bad?? Won't the epoxy fill the weave and dry area?

You have a lot more fiberglass experience than me, but I have been fiber glassing for over 45 years.

Regards
Tom
Reread my post. I said to do exactly that and to ise heat to help.

However, if it doesn't work; the glass might be contaminated and must be removed.

Re: Mark's C21

Posted: Tue Oct 09, 2018 9:40 am
by fallguy1000
Try rewetting first with heat even.

Then if that doesn't work sand it out with 50-60 grit.

Re: Mark's C21

Posted: Tue Oct 09, 2018 10:01 am
by fallguy1000
The other reality is my post was really rambling and sorry about that.

The thing about adding epoxy to an already cured lamination is it becomes secondary bonding.

And when we secondary bond, we usually roughen the surface. This can't be done within the layers that have already been wetted and on a boat bottom; we don't enjoy maybes.

Good news is S3 states a 72 hour primary bonding window.

So, I wandered and weaved. It was late and I was tired. Sorry.

Early, for a big dryspot, you can cut it out or try rewetting.

Later, it must be ground out.

Re: Mark's C21

Posted: Tue Oct 09, 2018 10:07 am
by mmachonis
I did this work on Sunday. Started at 11:00 am. So it will be 48 hours come 11 am today 9/9/2018. What do you suggest? I still have one day before the 72 hour limit.

Re: Mark's C21

Posted: Tue Oct 09, 2018 12:38 pm
by fallguy1000
Try wetting out some areas and see what it looks like.

Use heat if things are not flowing well.

If it looks like it is working. Do it all now.

Otherwise, if it seems like you aren't getting a good wetout. Stop the test and sand it all out tomorrow with 50 grit being careful to avoid sanding hull and patch with 2" overlaps as a secondary bond. You might want to make a thickened epoxy coating and trowel it flat if you have any sanding dips. I usually would for this type of repair. You let it gel up a bit and this helps avoid the dreaded dry suck.

By the way, this actually does look like dry wood sucked resin. Did you precoat the ply?

Re: Mark's C21

Posted: Tue Oct 09, 2018 1:32 pm
by Fuzz
If you do have to sand it off a 4 inch grinder with a 24-36 grit disk will make short work out of it. But, and this is a biggy, be very careful as the grinder will make a mess of things in a hurry if you are not careful. The late great Cracker called it a WMD for a reason.

Re: Mark's C21

Posted: Tue Oct 09, 2018 1:44 pm
by mmachonis
I've never used a grinder before, but I think I can be careful. When you refer to 24-36 grit, you are referring to 24-36 grit sand paper, correct? Do you get mechanical disks that are 24-36 grit or is it like an orbital sander where the 24-36 grit are sand paper disks that stick to the bottom of the machine.

Re: Mark's C21

Posted: Tue Oct 09, 2018 2:01 pm
by Fuzz
They make severial different types. A flapper disk type. A flat paper disk with a backing plate and some others.
I will post a picture in a few minutes.

Re: Mark's C21

Posted: Tue Oct 09, 2018 2:07 pm
by fallguy1000
flap discs are known as implements of destruction; I would not use the flap disc once you see wood and switch to sander at that point

Re: Mark's C21

Posted: Tue Oct 09, 2018 2:16 pm
by mmachonis
Thank you. Once I get it cut out, I will send new pictures to find out what to do next.

Re: Mark's C21

Posted: Tue Oct 09, 2018 2:30 pm
by Fuzz
Here is what I am talking about.
Image
They will eat glass and anything else they touch, :help:
Image
The black disks are something new I found at a boat shop. They eat glass like it is butter. Not good on wood but I have never seen anything eat glass like they do.

Re: Mark's C21

Posted: Tue Oct 09, 2018 3:12 pm
by mmachonis
So is there a specific disk I should be looking for? I see they are made by Zec. I went to their website and they have many types. They have Flexible, Semi-Flexible, and Plastic. Within those groups, there are different grades. Do I use the Silicon Carbide or the Aluminum Oxide abrasives? Will either of these cause a problem when later bonding with the next layer of epoxy?

Re: Mark's C21

Posted: Tue Oct 09, 2018 4:04 pm
by Jeff
Mark, I sent a note to Jacques to review your thread!! Jeff

Re: Mark's C21

Posted: Tue Oct 09, 2018 4:09 pm
by jacquesmm
I do not intervene when the thread is going in the right direction. I agree with fallguy:
Try rewetting first with heat even.
Then if that doesn't work sand it out with 50-60 grit.
I would not worry much about a secondary bond, that is more a problem for polyester but to be safe, do a light grinding.
I would do that with an angle grinder but them I am a fiberglass butcher, not an artist like some of you.
Whatever the grinder, open the surface with a grit 40 to 80 and apply more resin.

If the reason for the whitish spots is contamination, it will stay white. If that happens, you must grind down to the wood and apply a patch overlapping the good fiberglass.

Re: Mark's C21

Posted: Tue Oct 09, 2018 4:22 pm
by OrangeQuest
After you get your setup ready practice on something that you don't mind destroying! Like Fuzz stated "They eat glass like it is butter. Not good on wood but I have never seen anything eat glass like they do."
Keep your grinder moving and very little pressure. They are called angle grinders because you use them at an angle to the surface you want to grind.
Also because they remove so much so fast you can expect a small dust storm. This is what my area looked like after a few minutes of grinding epoxied glass.
3858

Re: Mark's C21

Posted: Tue Oct 09, 2018 4:30 pm
by Fuzz
I would go with the plastic for the black disks. I do not think type will matter too much. The flapper disks can be bought at places like Home Depot so that might be easier for you. 36-80 grit will all get er done just be careful as they will move a lot of material quickly. I am not sure I would use the Zec disks unless you practice some first and need to move a lot of glass.

Re: Mark's C21

Posted: Mon Jul 15, 2019 1:59 pm
by mmachonis
Hello all!

I hope you are all enjoying your summer. I've been slowly working on my C21 and I am about to put a skeg on the bottom. I read Jacques's post about skegs, strakes and spray rails. The only thing I didn't pickup on for the skeg was the height. I realize it should start a little forward of the middle of the boat and end a few feet from the transom. I was thinking about starting about three feet forward of the center of the boat with a 3 inch high by 2 inch wide piece of dimensional lumber rounded on the outside edge(feel free to make suggestions on which type of dimensional lumber) and run it to 4 feet from the transom where it would gradually rise to 6 inch high by 2 inches wide . What do you think?

Thanks.

Mark

Re: Mark's C21

Posted: Mon Jul 15, 2019 2:03 pm
by jacquesmm
That maybe a little too large. A 2x2 or 1x2 on edges is enough.
A 2x2 is really 1.5x1.5".

Re: Mark's C21

Posted: Mon Jul 15, 2019 8:32 pm
by mmachonis
So the skeg should be at its largest 1 inch wide by 2 inches high beginning 3 feet forward of the center and ending 4 feet before the transom?