Hi, Ron Short one first: (Since I seem to be "it", at least for now) >If there were a super lubricant that got you zero friction between the strings and pins, the string would, indeed, stay down on the bridge when at rest. When struck, the pitch would vary wildly as the string rendered back and forth freely through the pins ( the only resistance being kinks in the wire, and resistance chances corresponding to the changing pull angles resulting). The string would also be flailing up and down the pin with each hammer blow. There is no "super" lubricant. I was just wondering if reducing the friction could discourage hanging up, assuming the "creep" theory, for which there is no proof -- it's just my idea. In fact, everything we've talked about is just ideas, so far. You know how it goes: formulate a theory, gather evidence, test theory, cry, formulate another theory (repeat ad. lib.). I feel we are getting pretty far along in step 1 (formulate), and step 2 will have to be dealt with soon, if we're to get anywhere. Of course, step 2 is a LOT more work! Although it doesn't matter, since you are considering an imaginary system (with zero friction), I think you exaggerate the effect on pitch. I play the cello -- the string tension is very low, and the amplitude of string movement is _tremendous_. One gets a little "doppler-like" effect when playing very loudly on the lower strings, but not really very much. I worried, a long time ago, about whether lubricating bearings to improve rendering on uncooperative pianos would ruin pitch stability by lessening friction, allowing pitch swings such as you describe. So far, the answer has been that there's still enough friction for stability, and it's better to render more easily -- you get a "self-healing" effect as the unequal tension from the worst blows finds its own way back through. How low a level of friction the system would tolerate, I don't know. Surely other people know more about this than I do? >It's just like every other moving part we see in pianos. They were designed around naturally occurring friction and material performance/limitation ranges. There has to be friction for it to work at all. -- Ron Nossaman Agreed. Friction is necessary. The only questions are how much is optimum, and whether the optimum amount can be achieved in a practical, durable manner. My answer for your long post follows. (This is big enough.) >>Sure, you can double the life of violin and cello strings by rubbing pencil >>lead in the grooves at the nut and bridge; but contact with wood wasn't what >>I meant. I meant the metal-metal of the bridge pin and wire, which is where >>the friction seems to do the damage (making grooves, hanging up). I was >>thinking more along the lines of a drop of Protek, dabbed on right at the >>front bridge pin, while the bridge pin was new and unmarked. I was afraid of >>clogging the tone later, though, and unsure if it would improve the problem. >> >>Susan Kline Susan Kline skline@proaxis.com P.O. Box 1651, Philomath, OR 97370 Variables won't; constants aren't.
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