Boat plan index – multihull sailboats. support mike for maintaining small trimaran; ply plans; duckworks. 16 melanesia; james wharram; small cat; ply. Stock boat plans from lidgard yacht design, stock monohull and catamaran boat plans. Woods designs offer a range of sailing catamaran and trimaran designs plus a few powercats and some small dinghy designs for both home and professional boatbuilders.