DCA Cruise Reports Archive

Outrigger and Other Modifications on a 'Kirk/Mirror' Dinghy

This outrigger is there just to act for an old fellow, nowadays less nimble; as my crew sitting out for me. Its design?! - is of the 'seat of the pants' or empirical school. Like Topsy it just growed. Basically, it is the home-made plywood canoe which I used on the Reading to Littlehampton and on the Bath to Reading cruises. This actual canoe was laterally collapsed so as to become a float with a beam of fourteen inches with sides sloping down V-wise to a keel 2 1/2" wide midway and tapering each way to 1". It was built up with more plywood so that its 'deck' is level with the Mirror gunwales. Its LOA is eight feet, cut away fore and aft at an angle of 45° to give a LWL of approximately seven feet. Depth is eighteen inches.

It is attached to the dinghy by three struts of hoe-handle, bought from the gardening shop, of 1 1/4" diameter. All three go right through the outrigger and the extreme two are taken right through the dinghy buoyancy chambers, whilst the middle strut is higher and fastened just below the dinghy gunwale. Wherever struts pass through plywood they are securely fixed by passing through squares of hardwood which are screwed and glued with Cascamite.

The outrigger is at a more conservative distance outboard than with a normal catamaran or proa, the distance between centrelines of dinghy and float being only three feet four inches. This has proved adequate in practise, and does not put too much strain on the supporting struts. The round shape of the struts offers little resistance to any broken water hitting them. The outrigger contains the normal car-type battery for running the tiny electric O/B motor, and provides very welcome storage space. It is covered with a waterproof flap.

The electric engine goes between the two hulls having thus a free run in the stream; whilst the single leeboard is also in the clear channel, raised and lowered on a pivot protruding from the dinghy topside - the daggerboard and housing having been removed years ago to allow sleeping room aboard. The modified craft seems to sail just as comfortably on either tack, and indeed appears to beat to windward as well as the original monohull.

The eleven feet tubular Duralumin mast now works in a tabernacle on the keel, for easy lowering to pass under low bridges. The shrouds having been dispensed with, the mast fits back when raised again to be held between jaws about ten inches above gunwale level. Raising and lowering is done by means of a running forestay led through a sheave at the prow. And if ever in any danger from an extremely strong gust of wind, all the wind can be spilled from the mainsail by allowing the boom to swing right around the mast.

Sail area has been reduced by about 20%. Extra locker space has been obtained by fitting a second foredeck at almost gunwale level above the original foredeck. A waterproof spray-cover with a centre ridge is fitted above the foredeck, so tending to return any seas coming aboard to where they rightfully belong, and giving even more storage space. The hull has been completely GRP sheathed right up to the gunwales: cost me over £130 - DIY. Though it is most unlikely to happen, I would have little fear in committing the craft to open sea in suitable weather.