> The bottom is made of two sections of
> 1/8" Luan that have been glued together. That gives you 6 ply
> strength (actually 7 ply!!) with only 1/4" thickness.

I did the same thing on my hull (CC18), except the inside layer is ~1" smaller all around. I was thinking the seam tape would make the corners strong enough anyway. It worked fine and has held up, but I would use the specified plywood next time. All the additional bother wouldn't justify the savings. You need to buy twice as much plywood, use more epoxy, and lose paddling time.