@farmerman,
Forget the concept of kevlar. Im going with fibreglas coating over the wooden strips . It will make a more pleasing finish and itll be stronger and only 2 lb heavier when the varnishes dry . Anyway, I am having sewcond thoughts about my skills as a kevlar craftsman. The stuff needs to be measured more carefully because of shrink curing. Its like porcelain in that respect, Ill have to expect and handle a 5% or more shrinkage (as a function of the temperature).
ANyway, kev;lar can be kicked in whereas ribbing covered with the redwood and other wood and coated with a fibreglas and clear gel, will allow a wooden finish look. Curraghc=s are classically a skin or canvas covered boat but that isnt cast in concrete and itll give me a chance to show off my jointery.