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CrazyRussian
10-10-2002, 10:10 PM
Recently I become an owner of old wooden (plywood/epoxy) A-class catamaran – the light racing boat
Boat made of thin plywood covered with epoxy and has a strip of glass below waterline. It’s covered with paint. I sailed it extensively thoughout summer and fall. Inner sides of the hulls(I mean sides under trampoline) got a lot of cracks – compression loads from stays and sailing while flying a hull, my weight while righting a boat from capsize as well as age of the boat – all are contribution.
I’m not intending to use that boat for racing anymore – it’s not comparable to newer, lighter carbon fiber boats, but I want to convert it to very fast, light, wet camper cruiser. Well, and use it to race in Watertribe cruising Challenges www.watertribe.com. (http://www.watertribe.com.)
I don’t have any wooden/fiberglass boat building experience, but I do have a lot of boatbuilding skills in aluminum and PVC inflatable - here is a picture of my previous boat http://www.katamaran.ru/techno/rubber/photo/XWVD_023.JPG

After long lurking in that forum, as well as in many others I come up with a plan
1. Sand off all paint.
2. Cut storage hatches in the middle of the hulls (square ones)and access hatches in the bows for air bags
I have already two round hatches in the hulls next to crossbars for disassembling a boat
3. Soak hulls with penetrating epoxy.
4. Locate every single crack and reinforce it with a strip of a glass
5. Reinforce openings for hatches with a glass
6. Cover inner sides of the hulls with two lays of 2oz S-glass and outer sides of the hulls with one lay of 2 oz S-glass
7. Sand, fix all dents, repaint it with two part polyurethane marine paint

Do I miss something in this plan? Is 2 oz S-glass will be sufficient? I want to keep boat as light as possible and it doesn't have any glass on the sides now.
Do I really need two lays of fabric on the inner sides? Should I use 4 oz S-Glass? How much weight will I add? Hulls are 17 ft long and very skinny.
Any other ideas how to make a boat stronger?
Are where any rules of thumb for how much epoxy I need?

I really appreciate any input and I thank everyone in advance. I need a reassurance before I start buying materials. Hopefully you were able to understand me, English is my second language.

Vladimir

formerlyknownasprince
10-11-2002, 03:55 AM
Ughhh - too much extra weight.

Just fill the cracks with epoxy, paint and sail. if it cracks again, just fill the cracks with epoxy, paint and sail. If it cracks again, just.........

Keep it simple.

Ian
Owner of a very old plywood 20' Tornado B Class catamaran.

Mr. Know It All
10-12-2002, 11:19 AM
Welcome to the Forum Crazy Russian. Nice boat you have there.Thanks for posting a picture.
Peace---> Kevin in Ohio

Mike Field
10-13-2002, 07:18 AM
I've no experience of my own, Vladimir, but Ian's suggestion sounds about right to me. Just keep it nice and simple.

I echo Kevin's welcome to the Forum, too. And please don't apologise for your English. It's very good. (Speaking for myself, I don't even have a letter of Russian,,,,)