This directory includes all of the plans that are specifically designed for stitch and glue construction. the rc model x-1 is an inexpensive way to try out this. Hi milos, plywood used for kayak on pictures and videos is a regular one. this same non waterproof plywood is used in doubletrouble too. and for more then a 3 years. Owner and ceo john c. harris manufactured some of the very first clc kits in 1994. long before that, he had a fascination with small boats and boatbuilding..