Abstract: Stepping and un-stepping of a sailboat mast, of the un-stayed type that is supported only by a receptacle configured in the sailboat structure, are facilitated by a hinged core that is easily retrofitted into the foot of the mast. The core includes a two-part locking hinge that, when the mast is elevated up out of the receptacle in process of stepping or un-stepping, serves to keep the mast upright with its base held aligned in location above the receptacle. Then the hinge, located at the foot of the mast, can be unlocked to allow the mast to be tilted down to any desired angle, where it can be easily removed. The system enables one crewmember to easily step or un-step the mast manually on sailboats up to about 30 feet in length, optionally assisted by a small lifting winch that can be rigged on board.

Abstract: A catamaran type water craft having two tandem pairs of scissors-like folding mechanisms disposed between and pivotally connecting to the opposing upright surfaces of adjacent, juxtaposed hulls. The folding mechanisms comprise two pairs of overlapped cross-linked beams joined about central pivot joints. A pair of cross-linked overlapped forward bow beams can also be provided, arranged so as to rise at an increasing angle to the water craft as the water craft collapses. When the boat is collapsed, the cross-linked beams fold like closing scissors to bring the opposing hulls laterally together, and the bow beams are drawn together, allowing the catamaran to fold to a width that can be transported by a truck or placed in a marina docking slip with the mast in its upright position. A mast is located in the pivot structure of the forward pair of crossed overlapped links.