| The problem that keeps cropping up for me is payload.
I don't know this is true. I assert that it is cheaper to build in foam and glass, assuming Intelligent Infusion. One still has to glass both sides of the plywood or the foam. Infused glass and foam takes much less epoxy, and that is the most expensive item. No throw away frames or jig to build or align, just a flat table and sawhorses. Certainly work saved counts for something.
|A proa will not fulfill my criteria for the same reason a trimaran won't,
Asymmetry doesn't bother me, in fact I'm attracted to it. However it really doesn't work to put the mast in one hull of a cat. I don't see why not, assuming there are no headsails with sheet leads to leeward of the hull. The original Elementarry had a deck sweeping boom which was fixed to the mast. We never caught a wave, but when the hull was flown far enough, it would hit the water and could not be eased, resulting in a capsize. The solution is a wishbone boom high enough off the deck to not hit crew's heads and to give visibility underneath. The weight of the rig is relatively low. It is not necessary to live in the opposite hull, just store some heavier items there. Anchors are the obvious ones, and a decent fall for the chain and warp into the depth of the hull rather than the bridgedeck is a bonus. Batteries and tools will usually make up the rest of the weight balance.
I like the one seam, as it would be covered by the 6" sacrificial wood beaching keel I envision. Not all beaches are sandy and rock free.I am a tyres for fenders fan as they are cheap, can double as sea anchors/drogues or towing springs, provide something to sit on on rocky beaches and something to bounce on on surf beaches. If the hulls are shallow and rockerless tieing them underneath is quick and easy. Beaching keels need to be very strong (perhaps impossibly) to handle the boat being washed sideways in a grounding. They make scrubbing more of a chore, slow the boat (more wetted surface) and increase the draft to the point that sitting on a surf beach in water shallow enough to have little destructive power may not be feasible. They also increase the likelihood of tripping in large beam seas. | What I see as the most realistic build system is to build a three dimensional mold of an entire hull side on it's side on the floor or a table using temporary formers, stringers, and flat sheet material with a suitable gloss surface, the intersecting corners being radiused, and sanded smooth, as well as the joints, and any fasteners. The entire thing coated with a mold release, and the layers of the sandwich added and infused ........... no small undertaking. The knuckle.... thanks, that was the word that I was looking for..... and half the bottom, more or less lock in the contour. Pretty much how it is done, but there are a lot of labour savings you have missed. | The second alternative of course is to just build 3 long flat panels for each side of each hull, plus the bottom and have full length seams. A far simpler method, but far more finishing labor.... at least 6 seams in each hull, plus the seams for attaching the coach roof bridge deck, and bridge deck cabin, etc........... |"idiotic infusion"??? Yes. ;-) Yep. I think I might prefer the inherent dumping of a gust by the mast proper, via flexing. Or a greater righting moment. But an automatic sheet release makes sense, but I don't know how they work. Or how expensive or durable they are. Do y ou? T he latest iteration of our wand released sheet is near free, near idiot proof, has little to go wrong, works at a preset angle of heel or pitch and works even if the sheet is jammed on the winch or wrapped around the crew's ankle. |
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Posted by: Rob Denney <harryproa@gmail.com>
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