Changeup camp cruiser catamaran

05 September 2008     Editor    0 Comments.

The slider is the best pitch in baseball.—Ted Williams

Changeup is a riff on Ray Aldridge’s brilliant beach cruising cat, Slider. I hesitated to publish these drawings at first, since they are an obvious take-off on Ray’s design, but imitation is the sincerest form of flattery, so I hope Ray takes them in the spirit intended, which is one of respectful admiration.

Slider answers almost every single desire of my beach cruiser fantasy: Twin hulls, shoal draft, simplicity, dock-like stability, ease of launching, usable space, cargo capacity, sailorman rig, and an aesthetic that reaches deeper than the latest multihull fad. The only problem - and this is ONLY a problem for my testosterone/adrenalin driven ego - is that it tops out at 7 knots.

OK, I admit I want it all - a beach cruiser that will outshine the Mona Lisa and outpace the Enterprise. But given my economic and scientific station, breaking warp (knot) 12 would suffice. The only way I can see to break that barrier is to get the whole crew behind the initiative, so when the breeze kicks up, all hands to windward!

Changeup is designed to accommodate both crew in the windward hull, when conditions merit. The idea is that sailing in light air (the predominant condition in my sailing range) will see each of the twin crew within their respective hulls. But if and when the need for speed arises, then both bodies may be accommodated in the windward cockpit, thus providing the potential energy required.

The rig is the sliding gunter w/ curved gaff, a scaled-down version of Manu Kai. Mast height is a manageable 19’, and the 190 sq. ft. rig may contain up to three reef points.

The hulls are asymmetrical, and happily do without boards. Leeway resistance is provided by the hard chines, enhanced by chine-runners (see Matt Layden’s Paradox and Bernard Kohler’s KD860). The asymmetrical hulls position the buoyancy as far outboard as possible, gaining a few more inches of righting moment, and with a beam limited catamaran, every inch counts.

Changeup is 8’-6” wide, which is the only choice for a small boat that expects to be kept on a trailer - and used often. That said, I might be tempted to make a pair of 10’ beams to fit when the boat goes for a cruise of a week or more. The extra trouble would be worth it.

 

 concepts / catamarans 

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