This boat is easy to build using our downloadable boat plans. our boat plans are available for instant download so you can start building right away.. These free to download wooden boat plans (pdf) were first published in magazines such as "popular mechanics", "popular science" and the "boat builder’s handbook".. 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.