Spira international wooden boat plans. following are the stock plans available for the various types of boats, separated into the different categories.. Links to boat plans some free boat plans, boat building information including plywood stitch and glue. full range of boat plans from sophisticated yachts to plywood. Free plans: absolutely free plans (links to free online boat plans) ariawood boat works (plywood punts, jonboats and one-sheet boats) architectura navalis mercatoria.