Power catamaran plans and kits, catamaran plans , bruce roberts web site offers catamaran boat plans and catamaran boat kits for fiberglasss and aluminum boat designs, cut to size catamaran kits, part built boats or complete boats.. I’m interested in building a catamaran about 40 feet long. however, so far all the design plans i can find are in the $1000’s, and i’m having a hard…. How to build a catamaran fast and cheap 30 foot+ catamaran! plans this one of the builder out enjoying his new boat. leon has been building.