Richard Brekne wrote: > Ron Nossaman wrote: > > > >>But the main problem has always been finding something > > >>that didnt get in the way of regulating the standard capstan. This > > >>solves that problem. > > > > > >Again, congratulations. > > > > Has this been tried in actual hardware, or just as a vaporware conceptual > > exercise? There's a considerable gap between magnets in the drawing, and > > the inverse square law of magnetic field strength would indicate to me that > > you'd need magnets of considerable size, and mass, to have much effect with > > this sort of gap. I think I'd like a performance report of the prototype > > before any discussion. > > Just as an example, in a as simple as you can get mockup using hobby magnets available at your nearest hobby shop I have recorded the following a couple weeks back Renner action model, no whippen assist spring, FW of 30.6 grams Without Magnets DW 52 UW 30 With Magnets DW 46 UW 27 Four magnets Ø15mm x 2mm thick were used with 3 of them attached to the keystick, and 1 attached to a dowle made out of a bit of hammer shank which was mortised into the underside of the whippen. The distance between opposing magnet faces was about 3 mm and they were centered 15 mm front of the capstan. Together the 4 magnets and the dowel added 10 grams of dead weight to the system... yet despite this and the very rough character of the mockup I achieved a 4.5 lessening of BW and a 1.5 gram reduction in friction. Nice thing about this is that I droped 6 grams of DW and only 3 grams of UW. Course these magnets are cheap, inneffective and too large around to begin with. But as I said the basic concept is well demonstrated. With appropriate magnets and an nicely engineered execution this idea will work just dandy. Cheers -- Richard Brekne RPT, N.P.T.F. UiB, Bergen, Norway mailto:rbrekne@broadpark.no http://home.broadpark.no/~rbrekne/ricmain.html http://www.hf.uib.no/grieg/personer/cv_RB.html
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