Ron Nossaman wrote: > >Then put a 45 gram weight on the front of the key and begin to screw down > >the whippen magnet so that it gets closer and closer to the key. At some > >point the key will just start to move on its own. > > And as it does, the distance between the magnets increases and the touch > weight does too as the magnet repulsion lessens. The down pressure from the > repulsion on the back of the key lessens too, but to a lesser degree > because of the leverage differences. Actually, the distance between the magnets is so stable that I dont think you can notice this with conventional UW/DW measurements. Tho there is a slight difference in the amount of vertical rise in the whippen at this point compared to the key at this point to be sure. In anycase...it doesnt affect the motion characteristics of either measurement noticebly. > First class lever in the key, second > class lever from the magnet lift of the wippen. Not sure I follow you here. A second class lever is one in which the fulcrum is at one end, the load in the middle, and the input at the opposite end. Seems to me that the real capstan is still doing the bulk of the work, and this is providing a suppliment to this. > From a play standpoint, > that shouldn't be a problem since the increase progression should be > shallow and smooth, and everything is already moving. There is one more > thing though. You have a second class lever doing the lifting, but you also > have extra inertial mass on both the second class lever (key) and the third > class lever (wippen). Where the magnet lift is a second class lever, > providing a mechanical advantage, the inertial mass presents a third class > lever and an increased penalty. The weights involved here may not prove to > be a significant problem, but it at least needs looked at. Still unclear what you mean... but I will think on it. In the meantime... total weight involved (now that I'm down to three magnets) is about 4 grams. With 65% on the key and the rest on the whippen. > Oh, and non-magnetic capstan tools. If it works out, you can also claim the > advantage of automatic paper clip control. Grin... yeah.. I noticed that. Defininatly have to have non magnetic capstan tools. Hadnt thought of the auto paper clip vacum effect tho... :) Thanks for your thoughts. I will ponder them seriously. Cheers RicB -- 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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