Green valley boat works – builder’s notes: making gunwales. the subject of gunwales has also generated a lot of questions, ranging from the simple to the complex, and. Following swedish small boat designer/buider/sailor sven yrvind’s blog has given me confidence to consider building my boat of a foam core glass fibre sandwich. Canoe video resource. paddling canoes, electric canoes, sailing canoes. drop in rigs to make any canoe work as a sailboat..