LM18 Madison Wi Building questions

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Cbuf
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LM18 Madison Wi Building questions

Post by Cbuf »

Based on somebody's recommendation, I'm going to have one thread going for building progress and one thread for all my questions.
So here are my current questions

1. I taped the seems in my last work effort. I used Slow hardener for the Marine Epoxy system, do I need to worry about "blush" or just go right over the top. I do have some minor sanding to remove some burring edges.

2. Reading other threads it sounds like I want to add my skeg prior to fairing, is that correct?

3. Skeg material. What type of wood or materiel should I use, that can be found at a big box store (Like menards)? I read the recommended size was 1" by 1". Is that correct?

4. My roll of cloth is 60" wide, but my glass schedule calls for over laps on the keel, and sides, which means I have to cut the 60" cloth the long way. Is there a recommended process to doing this while keeping fraying to a minimum?

Thanks

Cbuf
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See my LM 18 build here.
viewtopic.php?f=12&t=64254
See my LM 18 Questions here.
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Reid
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Re: LM18 Madison Wi Building questions

Post by Reid »

Cbuf,

1. The MarinEpoxy Slow hardener should not blush under normal working conditions. Simply run your hand over the tape after it has cured. If you end up with a watery/oily residue on your fingers then simply wipe down with some warm soapy water. I used slow hardener in the shop today, it was 85+ degrees and humid and have yet to come across any blushing.
2. The skeg can be added before or after fairing. I installed my skeg on the FS18 after a round of fairing with the blended filler and one round with Quick Fair. I did this so the skeg did not get in my way while I was sanding with my long board.
3. I used some really dense foam for my skeg that was coated with epoxy and will later be coated with graphite. Wood would be fine to use as well.
1"x1" would be fine. I would keep it at least 18" from the transom as to not interfere with the prop.
4. Did you buy the cloth from us (Boat Builder Central). If so, our 12 oz. biaxial is 50" wide. Regardless, just follow the lamination schedule Jacques has laid out. Yes, you will need to cut the cloth lengthwise. We have a nice set of electric sheers at the shop but we cut a lot of cloth every day. I would invest in a good set of fabric sheers. You can find these on Amazon or any craft store. Don't be overly concerned with the ends fraying, they will be covered up when you fair the hull.

Progress looks really good so far! Keep it up!

-Reid
Someone asked me, if I were stranded on a desert island what book would I bring... "How to Build a Boat."
- Steven Wright

fallguy1000
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Re: LM18 Madison Wi Building questions

Post by fallguy1000 »

Cbuf wrote: Fri Jun 28, 2019 1:44 pm Based on somebody's recommendation, I'm going to have one thread going for building progress and one thread for all my questions.
So here are my current questions

1. I taped the seems in my last work effort. I used Slow hardener for the Marine Epoxy system, do I need to worry about "blush" or just go right over the top. I do have some minor sanding to remove some burring edges.

Sanding is required on all epoxy if you miss the primary bonding time window, or if the epoxy blushes, or if it is too rough to go over.

2. Reading other threads it sounds like I want to add my skeg prior to fairing, is that correct?

I prefer all structural work completed prior to fairing; there are some instances where this can vary. I have a section where I need to cleat the hull and it needs a ridge. Might do the ridge later; probably not.

3. Skeg material. What type of wood or materiel should I use, that can be found at a big box store (Like menards)? I read the recommended size was 1" by 1". Is that correct?

Just avoid any Menard's foams.

4. My roll of cloth is 60" wide, but my glass schedule calls for over laps on the keel, and sides, which means I have to cut the 60" cloth the long way. Is there a recommended process to doing this while keeping fraying to a minimum?

If you have to cut the fabric; you can remove the edge threads and create your own salvedge. But determining overlap locations is preference. Most overlaps are 2".

Thanks

Cbuf
My boat build is here -------->

viewtopic.php?f=12&t=62495

fallguy1000
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Re: LM18 Madison Wi Building questions

Post by fallguy1000 »

Most secondary bond tests show that a wire wheel is the best substrate prep. However, most of us would damage the substrate with a wire wheel. I prefer 40 or 60 grit papers for sanders, or I like 36 grit floor paper for hand work.
My boat build is here -------->

viewtopic.php?f=12&t=62495

Cbuf
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Re: LM18 Madison Wi Building questions

Post by Cbuf »

Is quick fair the same stuff as total boat total fair? The long description of each it almost exactly the same. Also, I have the BBC fairing that I'm going to use for the first pass, how how much quick fair should I get for pass 2, and 3? Also, if I want 3 layers of graphite on the bottom, how much graphite do I need?

Thanks
Cbuf
Attachments
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Screenshot_20190704-182323_Chrome.jpg
20190701_162056.jpg
20190701_162054.jpg
See my LM 18 build here.
viewtopic.php?f=12&t=64254
See my LM 18 Questions here.
viewtopic.php?f=2&t=64299&hilit=lm18\
Finished Boat Here
viewtopic.php?f=25&t=65173

piperdown
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Re: LM18 Madison Wi Building questions

Post by piperdown »

Quik Fair and Total Fair are not the same thing although they do the same thing. Like Silver Tip epoxy and Total Boat epoxy, both are epoxies and do the same thing but they are not compatible for wet on wet and would have to be fully cured and sanded prior to switching brands.

Quik Fair is a 2-1 ratio of A to B. Total Fair is 1-1 of A to B. I wish Quik Fair did the color thing like Total Fair did. Quik Fair is a brownish color and the hardener is white and the whole thing doesn't change color all that much. A uniform green like Total Fair would be nice to show complete mixing. I haven't used Total Fair so don't know how good it is but Quik Fair is a dream to work with. Very smooth and creamy texture and easy to sand.

If your initial pass with fairing and sanding are good then it doesn't take much Quik Fair for coat 2 or 3. For example my GF16 I've got the port side done mostly. 2 passes with the BBC fairing material with sanding. I've made 2 more passes with Quik Fair and out of a quart kit used less than 1/2 cup material and it hardly looks like I used much when opening the containers.

You can get a quart kit initially and go from there. If you decide you need more then Jeff and Reid will have it to your door in no time.

Not sure on graphite since I haven't gotten to that stage yet but for the bottom of my boat I'm guessing I'll need about 12 ounces of graphite for 3 coats or 14 for 4 coats. Since I'm not exactly sure I figure I'll just order 1 lb from BBC and go from there. If I need a bit more I'll just run down the a hardware store and grab a 2 ounce kit (used for dry lubrication). Heck I might have some left anyway on one of my shelves, used to use it for the wheels on the cars my boys built for the pine wood derby when they were in cub scouts.
Eric (aka, piperdown)

"Give an Irishman lager for a month and he's a dead man. An Irishman's stomach is lined with copper, and the beer corrodes it. But whiskey polishes the copper and is the saving of him." --> Mark Twain

fallguy1000
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Re: LM18 Madison Wi Building questions

Post by fallguy1000 »

fyi

When I mix quikfair, I used medicine cups, two for the A and one for the B.

I fill them, look at them, then dump them.

So far no mix errors.
My boat build is here -------->

viewtopic.php?f=12&t=62495

Cbuf
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Re: LM18 Madison Wi Building questions

Post by Cbuf »

Question I ordered the marine epoxy kit for the lm18, and I think the numbers might be off on the amounts needed. The kit has 8oz of blended filler. That wasnt enough for the first pass to cover the bottom and sides. My mix was the consistency of maple syrup thicker for the sides. I think the epoxy gallons could be off as well as I have used more than half of the 9 gallons.


It could be that I’m heavy on epoxy, but I have been scrapping at each lay with a 6 inch plastic knife, and my burn bucket is only about a quart. The burn bucket is where I dump left over epoxy, scrapings, and excess glue.

Anybody else building the lm with similar experiences?

Either way I just ordered a bunch more stuff.
Thanks
Cbuf
See my LM 18 build here.
viewtopic.php?f=12&t=64254
See my LM 18 Questions here.
viewtopic.php?f=2&t=64299&hilit=lm18\
Finished Boat Here
viewtopic.php?f=25&t=65173

piperdown
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Re: LM18 Madison Wi Building questions

Post by piperdown »

Cbuf wrote: Mon Jul 08, 2019 1:40 pm Question I ordered the marine epoxy kit for the lm18, and I think the numbers might be off on the amounts needed. The kit has 8oz of blended filler. That wasnt enough for the first pass to cover the bottom and sides. My mix was the consistency of maple syrup thicker for the sides. I think the epoxy gallons could be off as well as I have used more than half of the 9 gallons.


It could be that I’m heavy on epoxy, but I have been scrapping at each lay with a 6 inch plastic knife, and my burn bucket is only about a quart. The burn bucket is where I dump left over epoxy, scrapings, and excess glue.

Anybody else building the lm with similar experiences?

Either way I just ordered a bunch more stuff.
Thanks
Cbuf
I have yet to read any build threads that said the recommended amounts were enough, regardless if they bought the kit or just bought as they went based on the building plans, mine included. And I've read through the build threads extensively.
Eric (aka, piperdown)

"Give an Irishman lager for a month and he's a dead man. An Irishman's stomach is lined with copper, and the beer corrodes it. But whiskey polishes the copper and is the saving of him." --> Mark Twain

Reid
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Re: LM18 Madison Wi Building questions

Post by Reid »

Cbuf,

When we build out our Epoxy kits we do so with the experienced builder in mind. This way an experienced builder is not left with extra epoxy. Novice builders have a tendency to use too much epoxy when wetting out their fiberglass. Keep in mind also, the plans for the LM18 don't call for the 12 oz. biax cloth to go all the way up to the sheer line. This has definitely used more epoxy. That being said, most builders prefer to go all the way to the sheer line with the fiberglass.
Lastly, I will say that we ALWAYS keep our shipping costs to a minimum. We don't think it's right to make a profit from our customers from shipping costs. If you need to order more materials, try and get them at the same time to save on shipping but please know that we will do everything we can to help our our customers/builders!
The LM18 is looking really good! Keep it up!
-Reid
Someone asked me, if I were stranded on a desert island what book would I bring... "How to Build a Boat."
- Steven Wright

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