Having the idea that boats in general go the wrong way was one thing and probably the easiest way to have sorted that was to get a conventional boat of good tear drop footprint and rig it back to front, adjusting the attitude of the keel, mast step and engine appropriately.
That would have been modest in cost and if all failed the adjustments could have been reversed and one would have been left with a standard boat.
In fact it was the unwitting use of reverse in a new boat where the logged speed was eight knots against her forward speed that spurred the present attempt.
However obfuscation raised its head by my having to do this build in the manner of an origami construct - not intentionly so but it could be seen as such - making a boat from a single sheet of thin but springy material alone after making appropriate releasing cuts to form and relieve folding stresses.
This was the back bone of the model I built, some three feet long and which is shown below ....................
Well stabised inside along its bottom with lead (shot and small billets) and tested in the Serpentine here in London, it performed remarkably well. Tethered by a fine cord, at both fore and aft, it showed an impressive performance in both directions in terms of slipping through the water. The directional stability was, hands down, best when pushed (for that was the motive power) round end first - going in as straight a line as one could immagine - sharp end first the craft rapidly veered to one side or another.
The concept might be more rapidly envisaged by pushing a light bulb, held baynet end up two or three feet under the water and releasing it. In an instant it tumbles so the bulbous and most boyant end is upper most and exits the water to some height very much like a whale or porpoise.
I took the model to a somewhat more rough 'sea', the river Hamble where it again slipped through the turbulance gracefully.
Enthusiasm so armed, I ventured to have the model tested by the naval people in Southampton.
The cost of such testing was going to be some £2300. Foolishly I thought I could build a sizable 'model' that I could actually sail and test for that and so from that I embarked on the present folly.
The heading here mentions 'challenges'. I best list some of the issues and then hopefully some sense can be made of this note.
Optimism - The point of the build of this boat was to make a hull in 'an afternoon' pretty much the way I shape up a version from stiff paper in a 2 minutes. The single sheet of such paper was to be replaced by a single sheet of aluminium 6 metres by 3 metres. I couldn't get such a sheet or so I thought. So I fabricated that sheet from 4 sheets by margin overlap and a regime of riveting - 3 rows staggered.
Allowing that these so formed transverse seams had to be folded only a small fraction of the rivets were put in place accepting that in the folding the different diameters imposed on the overlap by folding causing a certain amount of shear in these 'tacking' rivets. After the definited bending and folding of the sheet the remaining riveting would be completed.
This riveting was meticulously planned, carried out on the floor of the workshop and this itself was quite backbreaking and dreadfully boring over a period of about 6 weeks.
All this could have been aborted by better investigation at the outset.
I could have got the sheets seam welded - it would have had to be edge to edge to avoid shear to shear or distorsion had it been done by overlap - it crossed my mind, and I made some attempt to investigate the possibility but 'the slog of riveting' was not so apparent and that what I chose - This was such a major mistake that it has has reverbrated through the entire build to date. Riveting is boring, hard work, lonely, in that really there was really only room for one on that raft of sheets, and a job that still has to be meticulous in planning and execution. It undermined at the outset the more I set out to propose being that of ease of build.
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