Hi, Paul,
I use Hypalon cloth as the hull, and use pleaster (w/PU coat) cloth as deck.
But how to sew them together and waterproof?
I would not like PVC because PVC feels freeze and very heavy.

: Tent makers have the same problem with sealing seams after the fabric of the
: tent is sewn. They have materials for sealing seams. You might check for
: such materials. Otherwise, you need a flexible paint or rubber coating
: that will stick to the fabric and seal the holes from the needle.

Hypalon looks difficult to stick any material, would you please suggest some material for Hypalon's hole's seal?

Do you know what's method does Nautiraid use? Or Klepper use now? Or Fujita use?

Thanks so much!

Sincerely

Ning