How to build a small sail boat. these plans are for a small sail boat called the biloxi dinghy. former builders claim it’s a great design.s. from the plans:. Free sailboat plans for the backyard home builder, build your own wooden sailboat using these simple plywood designs.. A site dedicated amateur boat building, with an on-line catalog of boat plans and kits, bulletin board, project registry, builder photos, news letters, how to pages.