: Last summer I designed and build my own skin on frame kayak. It turned out to
: be very, very tippy. It is 12' X 20" with a hard chine bottom. I sit
: about 4" inches off the bottom, so I know that if I close that gap it
: would be less tippy.
: Anyway, I want to build another one this summer. What design changes should I
: make to make it less tippy? Thanks for your help! Clint

A large factor in the instability is obviously your seat. Get lower. Other changes: if the boat is 20" in overall width if is probably narrower at the waterline. Try to make the waterline width wider. This can be done either by increasing the over all width or decreasing the amount of flare in the sides. The flare can be ajusted by moving the location of the chine.