Trimaran Folding Lock

Folding Lock-01

4th March 2014

Folding trimarans can and do fall over when the floats are folded in. This can happen on the water, in the pen, or on the trailer, usually as a result of wind load on the rig. For motoring with the floats folded it is recommended not to fully fold but to lock the beams so the floats are approximately one meter outboard of their fully folded position, or just outboard of the point where the float starts to try to fold in quickly.

One simple way to do this is to simply fit an aluminium strut from the deck to the underside of the beam. The strut can use a pole beak fitting or other quick release device at each end. The deck and underside of the beam might utilise a jockey pole ring or suitable padeye for easy attachment.

If the strut is being fitted to an existing design care must be taken not to drill into the structural cap laminate in the beam. For new builds this can be taken care of in the design and build stage.

The struts can be stowed below or taken ashore to minimising weight when racing.

Another way to achieve the same result is to lock the upper and lower beam struts with an interconnecting strut, and this might lead to a cleaner deck layout with less obstacles to stub your feet on.