Simplicity boats links of interest… = simplicity award winner! boat projects – kits & plans – information – supplies – software – sail stuff -. Cylinder mold multihull construction . cylinder molded multihulls have come a long way in the last twenty six years. by now in 2009 there are hundreds of cm built. Here’s the 1967 ayrs (amateur yacht research society) report on how the tornado, a "tortured plywood" boat, became the olympic catamaran. it was a major leap forward.