Holes

[predator]

I have a old boat that needs some small holes repaired and was wanting to put kevlar on it for strenght will be hitting logs from time to time.how would one go about ataching the kevlar to the old style fiberglass i have done fiberglassing before but never with kevlar.will try to post pics later.

[Deering]

Kevlar is a good material choice for impact protection - it has outstanding tensile properties, but is poor in compression. Because of that it should be placed on the inside of the hull rather than the outside - when you hit something, the outside of the hull is in compression while the inside skin is in tension, which is where kevlar will do the most good.

To attach it, you need to make sure the hulls really clean, free of oil/grease/wax... then rough it up with 80 grit sandpaper. Use epoxy to adhere it to the original hull. It's expensive, and may require special shears to cut it.

Do you hit logs often?

[predator]

hit
Do you hit logs often?
Yes the boat will be used with a go-devil rig in the grass and cat tails the grass is so thick you cant see under the water level and you find stumps and logs quite often so i am wanting to beef up the bottom of boat to help impact .

[gonzo]

A thick mat laminate is very good for impact and puncture resistance. Kevlar is brittle and it is used on thin laminates for light weight construction. A heavier, resin rich laminate is more forgiving.