Roger Jolly wrote: > >Greetings All, > I seem to recall reading some where that ribs are tuned by > some manufacturers in this area, by tapping with a mallet, and are then > sanded or shaved to a desired pitch to help smooth out tone quality in this > section. > I'm not sure of my facts, maybe Del would respond, or Jim Coleman Sr. as I > also think I saw this done in the Baldwin Cincinnati grand plant. Now that > was a couple of years ago. But I would be interested to know the relevance. > Regards Roger. > > > Roger Jolly > University of Saskatchewan > Dept. of Music. ------------------------------------------ Roger, Any long, slender piece of wood -- i.e., a piano rib -- will have some fundamental resonant frequency as determined by its length, its cross-sectional shape, its mass and its stiffness. Tapping a group of otherwise identical looking pieces of rib stock and listening to that fundamental frequency will reveal that their physical characteristics can change quite a bit from one piece to the next. Essentially the same information can be obtained by putting each piece into a test fixture and checking for the amount of deflection under some predetermined load. Having this information can be of some value in laying out ribs in a particular sequence according to their stiffness-to-mass ratio. -- ddf
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