: My experience with polystyrene, epoxy, kevlar & glass used to make sail
: boards was that the PS foams did not have enough edge strength to hold up
: to the loads of wave sailing, in particular wave jumping. A layer of 6 oz.
: kevlar however, made them indestructable even when the whole bottom was
: flapping loose from the foam.

: I would expect that kayaks are less heavily stressed than a sailboard so I
: would not worry too much about it. The main thing would be to put enough
: glass/kevlar on the exterior so that it is pretty much the single skin of
: glass that is doing the work and to not really too much on the foam other
: than to give the boat shape for glassing. Some testing of panels would
: probably suffice to design a layup. My very unscientific method is to
: layup 1' x 1' test panel and after they are well cured, I start smacking
: with various size hammers including a 16 oz, a 3 lb and a 6 lb sledge.
: Each of these will give you a sense of just how tough your laminate will
: be. Very little is needed to just hold shape and keep the water out. More
: is needed is you intend to bounce the boat off rocks. My sailboards with
: one 6 ox. layer of kevlar and one 6 oz. layer of E-glass were very rock
: proof.

: Craig

That's kind of what I was thinking. I seriously doubt that any kayak takes the sort of beating that a sailboard jumping off waves experiences. Wear and tear and the occasional point load from rocks are the primary worries. I may give one a try since the price point is right and it seems like it would be something different. I was thinking about a set of stitch and glue plan set...that way I could always come back with a plywood version of the same boat for comparison both in terms of weight, durability, and performance. The out of pocket expense for either wouldn't be too bad, depending on what plywood one goes with...