Open/dayboat, free sailboat plans. hobby kat. everyone who digs boating has heard of the hobie cat, the sleek little catamaran that burst on the scene and captured the attention of all the fast-action sailors.. Free wooden boat plans for other sailboats. back in the old days, there were a lot of simple plywood boat plans in magazines, most popular were sailboat plans, canoe plans and kayak plans.. Simplicity boats is about sharing information that helps people expereience the fun of boat building for the least investment of time, skills, or materials..