The Transition Rig idea arose in 1986 and was first applied to windsurfers, but in the late 1990s I began experimenting with free-standing rigs on dinghies. The first dinghy versions were mounted on a Mirror dinghy, and enabled pronation/supination of the rig as well as folding. This meant that control cables and the raising/lowering cables had to pass through the rotating mast base as close as possible to the axis of rotation on their way up the mast. The joints were moulded from composites and took a long time to make. These factors added to the complexity of the rig, but in some ways this early version is closest to the the original idea of a variable-geometry rig. I shall be describing it in due course, but first will introduce the much-simplified version that I use now.

The video shows the main features of this version - the rig is raised and lowered manually by way of a single operating strut, it is mounted on a rotating mast base, and the sail is controlled by a single mainsheet. The deck-level doors provide additional support for the rig when it is up. The front end of the wishbone boom rotates in relation to the mast segment it is attached to so that the lower part of the sail can take on the correct camber on each tack. The mast segments are made from aluminium tubing, and the joints from aluminium plates bent around the tubing and pop-riveted in place - ie: very simple and quick to make.