Seniors: Outriggers for a kayak

September-October 1994

This is an article from WaveLength Magazine, available in print in North America and globally on the web.

In our continuing efforts to bring you all the news in the paddling scene, no matter how bizarre, we offer the following account of a project by 74 year-old Ted Wilson.

First time in a kayak, made easier with pontoons

A couple of years ago I constructed a kayak from a kit using the stitch-and-glue method. The kit (from Pygmy Kayaks of Washington) contained all the necessary materials, including pre-cut, 4-mm marine plywood so that with surprisingly little work and money it got me into paddling. But then I bought a Triak (a sailing kayak with pontoons), which offered both stability for paddling in rough water and the ability to sail. With the new boat, which was much more versatile than the original kayak, the wooden boat became somewhat surplus.

But I got to thinking how the plywood kayak could be fitted with a pair of pontoons. The deck behind the cockpit is flat, so it would be easy to fasten a spar across it attached to a couple of floats. It would also be fun to make floats of my own design using the stitch-and-glue process. Since I had some epoxy left over and some eighth-inch plywood (doorskin), I decided to try it. The advantage of being retired is that one can indulge in any kind of activity, no matter how useless, without worrying about the time it takes or about making a living.

The floats were about the simplest design I could think of: boat shaped, with a V cross-section, symmetrical fore and aft, and with a flat top. This shape has only three seams to glue and tape. When fastened together, the three plywood faces form quite a rigid structure without any frames. One thing I worried about is that buoyancy is dependent on there being no leaks. (The floats for the Triak are filled with foam to maintain buoyancy regardless of a puncture to the skin.) However, with fiberglass tape on the seams, leakage would not be a problem.

Dimensions were chosen arbitrarily: the cross section at the centre is a 6-inch top and 6-inch sides at 60 degrees to one another, forming an equilateral triangle. The size was determined primarily by the 36-inch by 40-inch sheet of doorskin which I had on hand. The spar which connects the floats to the kayak was made from a two-by-four, eight feet long. Each float is secured by a single bolt and the spar is fastened to the kayak by two bolts. With captive nuts under the deck and captive bolts on the floats, the outrigger arrangement can be quickly assembled with just four threaded connections. The total extra weight amounts to about 12 pounds (and a lighter spar could be used).

Despite the arbitrary shape and dimensions, the floats work remarkably well. Each one provides approximately 10 pounds of buoyancy. Because they are at the ends of the 8-foot spar, the "righting moment" produced is ample to let me get out of the cockpit and sit on deck or even to stand up in the boat. The V-shaped section of the float produces a gradual increase in buoyancy as it is immersed, thus choppy water does not produce a slapping effect as would occur with a flat bottom. Also, the curved shape tends to immerse only a minimum volume as the floats barely skim the surface in normal paddling.

The floats might not be as satisfactory for use with a sail, however, since the flat top surface could scoop into a wave when fully immersed under press of sail. For such a purpose, it would be better to have a well rounded top to permit the water to rapidly drain off instead of pulling the float under.

But what good is it? The answer is: it's not much use for most kayakers. And it turned out to be more work than I expected. But there are some advantages.

A few weeks ago I had a visitor who had never been in a kayak and was concerned about capsizing. With the outriggers she soon felt secure. Also, the extra stability is good for taking photos, even in rough water. Anyway, it was an interesting project.