We designed and created model open boats using some of the methods we know are used to make traditional birch bark canoes. We only had glue and string to make the joins. We used PVA as a waterproofing for the skin if we thought it need it. It didn't work quite as well as resin and bear fat to close any leaks. Everyone made gunwhales as part of their framework but there was a mix of hull designs. Some had a distinctive V shape along the keel while others were the traditional open canoe flat bottomed hull. Most people modified their designs to some extent as they made the models, and everyone learned a lot.