The problem, is finding sacrificial boats to test.
The impact device is easy:
Tie a couple of old mattresses (to simulate whale skin) to the grill of an old junk car (that still runs) and ram the shit out of soon to be demolished boats.
I think one would learn pretty quick what works and what...
Not to throw shade on the feat, but a rudderless long/full keeler is a totally different ballgame than a rudderless fin keeler. And Colvin keels are some of the longest of the long.
I am reminded of Slocum's voyage where he reported that Spray would reliably hold course on any point with the...
Zenith Aircraft is another.
I do not know why they did not also use a one piece horizontal tail plane (stabilator). These are much more common than one piece rudders. Piper made zillions.
The Bristol Channel Cutter (and the Cape George) are full keel designs and are waaay easier to laminate than a typical skeg.
Most of the keel has shallow depth/generous width (about 1 foot +) and is a snap to laminate properly. However, the extreme lower/aft area is more difficult to reach...
Not so much.
I can't speak about the Westsail, but I have it on good authority (I work at the factory) that the Bristol Channel Cutter (and all the Cape George boats) are built thus:
Two piece mold, split down the centerline.
Before the molds are joined together, gelcoat and one or two layers...
Having a full length keel with much of it only a foot (.3 meters 😉) deep means that the following "beef-up" is probably moot.
I have always been skeptical of the connection between my keel bulkheads and the ring frames: It is a butt weld that, to my eye, looked like the...
Disregard my previous suggestion of running it "as-is".
I did not properly read your original post. I read it as you being able to get 3400 rpm, not the 3100 rpm that it appears you are actually getting. My mistake.
3100 seems to be more than "a little bit" over-propped.
The local Yanmar service guy told me that my non-turbo engine uses the same block as a turbo model (which has close to double the power).
He told me to not worry about the main and rod bearings. Pretty much bomb proof.
Back when I rode, I had the nutty idea to get something like an aluminum Jon Boat, fit it with retractable trailer wheels and tow it with the motorcycle. Then, at waters edge, load the motorcycle into the boat with the rear tire turning acting on a drum that is connected to a propeller...
Maybe I am not reading it correctly, but I thought DDW's main point about longevity was that it is strongly correlated to the total fuel burned (or horsepower produced) over the life of the engine.
It seems that as long as temperatures are within limits, the only downside of being over-propped...
How about an offset wheel that is mounted BEHIND the helmsman?
When seated on the Starboard bench, steering inputs feel natural with the left hand on the SIDE of the wheel.
But, when seated on the Port bench, the left hand grabs the wheel at the BOTTOM spoke, thus reversing the action, not...