Thanks for the quick replies, its very encouraging...
J Alani, I will ask Scott thanks.
Mark, Point taken, I did waste a lot of time and money with my stitch and glue canoe. But it was fun designing, solving problems and building. What a change from my day job at the bank ( used to be an engineer but banks pay better)
Rolf, I had heard a lot of bad stories about meranti ply in the US websites but I found the marine ply here to be of good quality. I went through several sheets when I built my canoe and there were no voids and good veneers used. Only thing is that the thinnest I could get was just under 4mm thick....and I dont think meranti ply bends as well as okuoume.
NCIK, thanks for the offer, I will take you up on that. I am thinking the underwater cross section should be semi circular and the plan view of the hulls should be 2 circular arcs. So if I put the equation of a circle into a spreadsheet and vary the radius until I get the arc i want, I should be able to get a table of offsets of the width of the hull every ft. Then I draw a semicircle at each point to get the mold frames.