Stitch-and-glue construction, along with the development of epoxy and modern mahogany marine plywood, has revolutionized and revitalized wooden boat building.. Welcome to spira international home-built boat plans. spira international offers a wide variety of different power, rowing, and sailing skiffs, dories, and other boat.  8′ puddle duck racer one design racing sailboat based on bolger brick. developmental class, defined hull, unlimited sail rig and underwater fins..