> Hank, When using luaun, is it necessary to use exterior grade or is plain
> old underlayment OK?

Hi Tom,

I never had much choice when buying the luan so I never asked. My first couple of kayaks were made from wall paneling. Being reinforced inside and out with cloth and the were edges well sealed, I never had any problems.

I now buy my 4' x 8' sheets of 3mm luan from a company that makes garage doors. I would presume that it is an exterior grade. The local mills and construction suppliers only stock the 5.5 mm.

I have always used the 3mm for the main construction and use 5.5mm for bulkheads and such. As I mentioned in my previous post, I often double up the panels cockpit area. This way I can keep the overall weight light and selectively strengthen where I want to.

I have never built a kayak for use in the ocean. Would I use 3mm luan for a kayak to play in the surf? Probably, but I would go heavier on the fiberglass cloth - 6 oz in and out.

I just read Randy Ames post and I agree with him completely - you can use economical materials and still come up with a top notch boat. I always ask to look through the "sale bin". Often you can find panels with minor defects (broken corners etc.) for reduced prices.