WOT: Dad's kevlar canoe major repair/rebuild, Any kevlar repair guru's? A few questions Options

[Mark Henry]

Over the winter I'd like to repair my dad's canoe. I know it looks bad, but the main skin is kevlar, the woodwork is cedar and fairly simple, plus there is enough bits to copy. I have the tools, my trade is cabinetmaking. Only thing missing to copy is the yoke, but the old one sucked anyways

The kevlar repairs will be the only thing hard-ish to do and this is where the question comes in....
Can I cut this in half and add 3 feet to the center?

It's a 15-1/2' canoe and it's looking like I need a 3 person canoe. If the wife was into it I'd get another canoe, but if it's just me and the 2 kids I'd rather have just one canoe. Most 3 person canoes are 18-19 feet.

Any tips would be welcome (IMG:style_emoticons/default/smile.gif)

[barefoot]

Disagree with prior post. Epoxy is easy to work with, just make sure you use correct resin/hardener ratio, easy to do using WEST system pumps as they give correct mix.
Epoxy is stronger than polyesther and makes a stronger bond.
Kevlar is very hard to cut, I went thru several pairs of shears before finding one that would cut the stuff. Using kevlar is not necessary, you could use fiberglass or carbon cloth for the extension, just have to use a bit more thickness with the glass. It might be a good idea to incorporate a foam or balsa core in the new area, this will make the structure much stiffer than a single skin of either kevlar or glass. hardest part will be to make a form to get the proper shape. Suggest laying visiqueen plastic sheet over a good section of present hull and then lay-up new outer skin over this. it won't stick to the plastic and will be a good match to the form needed. then support it somehow and add more glass, carbon, or kevlar to the inside to get the thickness you want. Fair it into the old hull in at least a 12:1 ratio.
Forget gelcoat as it doesn't adhere well to epoxy, To get a smooth outer surface, using WEST lightweight 410 filler mixed into epoxy and trowel thin layer over skin using wide drywall spreader. This stuff will sand easily to get finish you want.
here's sample of epoxy/glass over foam core engine box i did for sailboat project

barefoot

[Mark Henry]

Disagree with prior post. Epoxy is easy to work with, just make sure you use correct resin/hardener ratio, easy to do using WEST system pumps as they give correct mix.
Epoxy is stronger than polyesther and makes a stronger bond.
Kevlar is very hard to cut, I went thru several pairs of shears before finding one that would cut the stuff. Using kevlar is not necessary, you could use fiberglass or carbon cloth for the extension, just have to use a bit more thickness with the glass. It might be a good idea to incorporate a foam or balsa core in the new area, this will make the structure much stiffer than a single skin of either kevlar or glass. hardest part will be to make a form to get the proper shape. Suggest laying visiqueen plastic sheet over a good section of present hull and then lay-up new outer skin over this. it won't stick to the plastic and will be a good match to the form needed. then support it somehow and add more glass, carbon, or kevlar to the inside to get the thickness you want. Fair it into the old hull in at least a 12:1 ratio.
Forget gelcoat as it doesn't adhere well to epoxy, To get a smooth outer surface, using WEST lightweight 410 filler mixed into epoxy and trowel thin layer over skin using wide drywall spreader. This stuff will sand easily to get finish you want.
here's sample of epoxy/glass over foam core engine box i did for sailboat project

barefoot

Excellent info barefoot

I have a local source for kevlar and west system products. Price doesn't seem too bad.

Forget gelcoat as it doesn't adhere well to epoxy

The finish on the canoe is not regular mold and gelcoat smooth, in fact I think it's just painted. If I power wash it hard (3000psi from 2-3 inches) I can blow off the paint/gelcoat...whatever it is, down to the gold colour kevlar. The kevlar may be just a single ply, it's only .055 thick.