Bill Ballard wrote: > I agree that once you install the magnets, and enter their force > vector into the system, that in the dimension of mass, the leverage > has changed. As it must. In the linear (or angular dimension), > nothing has changed. So whatever lightening of the load the magnets > accomplish, this won't require resetting blow, dip and aftertouch. > Nobody is surprised anymore that these two measurements of action > ratio are independent of each other. > (Actually, it's just that the > weight-based measurement can be changed without altering the the > actual lever arms. It doesn't work the other way.) I think what you have to understand here Bill, is that you are adding two lever arms to the system. The keystick, tho remaining one peice of wood, becomes two levers in one. The keyfront--balancerail--capstan being one lever, and the keyfront--balancerail--keymagnet being the other one. Both are 1st class levers. The whippen, tho remaining one physical assembly, becomes two levers as well. The whippencushion--whippencenter--jacktop being the one, and in Rons analysis, the whippenmagnet--whippencenter--capstan being the other. The former being a thirdclass lever and the later a secondclass lever. He could have probably defined the whippenmagnet--whippencenter--jacktop as the << second whippen >> but perhaps that will make figuring the net affect more difficult. In anycase what he did works very well in figuring out the net leverage. We are indeed changing the lever arms in the sense we are adding two new ones at different locations. > > >It functions more like putting a secondary capstan and heel on the > >key and whippen then anything else... again except for the > >compressebility. > > Why is it doing anything more than placing an upwards vector right > next to the downwards vector at the capstan lift point. I thinks it > function very similarly to a helium balloon tied to, and lifting up > on the wippen. Except.... the force between the magnets pushes down on the key at exactly the same amount. Doesnt work like this Bill. Its not just a <<lift>> for the whippen. That would require a magnet fixed to a stationary point attracting the whippen magnet. > If one views the effect of the magnets as being just > another force vector, then it can be generalized as having a net > effect on the capstan. Well.. I think in general terms... thats what Ron did. Except its a double ended force vector and applies an equal force to the key at the key magnet as it does on the whippen at the whippen magnet. > When viewed in the dimension of mass, the > magnets simply make the second point at which force enters the > system, to lift the action parts. The first point being the front end > of the key. Try removing the real capstan and leaving a theoretically strong enough magnet with a defined magnetic feild range of exactly 5 mm. Beyond 5 mm no strength, but up to and including 5 mm full strength. Such a magnet pair would hold the whippen and keystick exactly 10 mm apart, and since this hypothetical magnet is strong enough as well as being so precisely limited in feild range.... it would not compress under the heaviest blow at the key. If such a magnet pair existed and was used thus.. there would be no significant difference between them and our present capstan/heel arrangement. That real magnets are somewhat more compressible then the above imaginary construct does not change the fact that their effect in this connexion that of a capstan and heel coupling that has a high degree of compressibility. > Yeah, I know, it's not fair of me to fire all this of after you've > gone to sleep. <g> You caught me after my morning coffee :) > > > Bill Ballard RPT > NH Chapter, P.T.G. > > "We mustn't underestimate our power of teamwork." > ...........Bob Davis RPT, pianotech '97 > +++++++++++++++++++++ > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives -- 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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