Ron, It helps alot to shed just a little light on this murky subject. Thanks a hole bunch!!!!!!!!<G> Joe Goss imatunr@srvinet.com www.mothergoosetools.com ----- Original Message ----- From: "Ron Nossaman" <RNossaman@KSCABLE.com> To: <pianotech@ptg.org> Sent: Friday, December 07, 2001 6:40 AM Subject: Re: Front Rail Felt Theory > > Is there any rhyme or reason for a billion > >different sizes? Or are different sizes made simply because the > >manufacturers can sell them. And folks that are bothered by these things sit > >in misery while they wonder in frustration: why? > > > >Terry Farrell > > Oh, that's simple. Just look at all the different sizes of key bushing > cauls that are necessary to fit all the different sizes of key pins that > have been used in the last 150 years. There used to be a formula, seldom > acknowledged, involving the average of the diameters of the front and rear > pins (measured front to back and side to side to account for ovularity), > divided by the straight line distance of the tips of the pedals from the > key overhang (if there is one), times the standardized speaking length of > C-8. This figure is then multiplied by the logarithm of the ratio of > overall piano height, to overall length front to back (this is why you tend > to see larger diameter punchings in grands), and marinated in a highly > proprietary constant that curiously shrinks the punching dimension to fit > the requirements of the piano. How this constant was arrived at has never > been divulged, but it has been long suspected to involve certain species of > mushrooms. The present abundance of apparently arbitrary combinations of > diameters, thicknesses, densities, and colors, merely indicates the > continued reliance upon and availability of these mushrooms. That is also, > incidentally, why the punchings should be kept under the keys where it is > relatively dark, and protected by the layers of accumulated loam. > > I hope this is of some help. > > Ron N
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