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by David Kagan - Stillwater, Minnesota - USA
A Home-Built and Home-Designed Trimaran Sailing Dinghy

Irascible was conceived as a prototype to test out some design and construction ideas before committing to designing and building a larger version. The dinghy is 8 feet long, ten feet wide, and weighs about 200 pounds. The initial windsurfing rig provides 6.5 sq. meters of sail area.

I've named the boat Irascible, which means cantankerous in a curmudgeonly sort of way. At this point, the sailing manners of the boat are totally unknown, so the name might potentially describe its personality on the water. If the boat handles well on the water, then it's obvious I named the boat after myself.

A few friends helped me set up the trailer. This took 15 trips to three hardware stores over two days. Glad to be done with that. About the 8th time you walk into a store in a two hour span, you start to look suspicious, eh? A little bit more trailer tweaking is needed next time the boat floats and then it's a keeper.

Irascible is floating for the first time here in about 4 feet of water. She sits very high and level in the water.

This is good. I was worried that she might settle down to her gunwales. That would be bad. I have a Minnkota trolling motor mounted to the rear crossbeam on the port side. The motor is locked so that steering is by tiller only. The motor is too close to the port outrigger to steer by the motor.

A large tool box is lashed to the port seat and holds the deep cycle battery, some tools, and my DNR registration. The box is vented liberally. Maybe I will lash a watertight counterpart on the starboard side for goodies or an emergency transponder. Will the boat sink?

I'm using the forestay as a tether here and am about to step on board the first time. At this point, I'm wishing I had put the nonskid pads on the outriggers. I'll need to tend to that, but stepping on board wasn't too slippery. Glad I noticed.

No, I didn't lose my main mast. The stub mast is for holding a windsurfing rig. There's no wind, so the rig stayed in my vehicle. Along with my keys, alas.

I'm drifting slowly away from the dock here on the St. Croix River wearing a physique molded by Taco Bell and my PFD. If my boat doesn't make it, at least I'll float. This national scenic river way has a current that moves about 3 miles an hour from right to left.

I'm sitting on the starboard outrigger and the outrigger sank only a few inches. This is a good sign for side to side stability. The stub mast crutch is still in place in the rear beam. My tiller handle is sitting in the mast slot.

I'm drifting downriver some more and tending to one of the three forestays. These are not needed to stabilize the stub mast, but provide easily accessible lines for dock maneuvering, lowering the stub mast in its tabernacle, etc.

The motor is still up, but it's time to see how the boat moves and steers under power.

Moving away under power now. I'm thinking I need twin Merc 150's? I'm being broadsided by the current and the boat is tracking just fine. You can see from the wake that slippage to the left (downstream) is negligible. The ability of the boat to resist downstream slippage is potentially a good sign as during sailing the leeward outrigger will be driven even deeper into the water. I'm relying on the deep center section of the outriggers and my large rudder for a large amount of my bite in the water under sail.

That's me, my motor, and my tool box filled with 40 pounds of stuff on the port side in the bottom picture. The boat is hardly tilted. I weigh slightly more than 40 pounds by the way, so there's quite a bit of ballast all to port.

The circular wake track in the top picture shows the boat turns pretty effortlessly and tracks well through the turn. Lower left shows my standing with all my weight over the center of the port outrigger. The boat is firm underfoot, further showing the side to side stability.

I'm back on the dock. You can see how level the boat sits in its neutral position.

If there had been wind today, the rig on the boat would have looked like this.

Irascible should be a fun dinghy but was conceived as a prototype to test out some design and construction ideas. I was originally thinking that a full size version would be 18 to 20 foot long (with appropriate rig selection, of course). But now I'm thinking that a 16 foot version a with more mainstream rig would provide ample room and performance for day sailing.

Ten feet of beam is bothersome to trailer. I ordered and have some components coming that will allow the beams to fold. The seats will be narrowed by about 6 inches. My cross beams are ten foot Superstrut beams, and the components I bought for folding are part of this system.