> Wouldn't the tuning pin fill with additional wire? > Paul C One would think, should one... After a whole lot of years looking for anything more substantial than instinct, intuition, rumor, and random guessing to verify one way or the other whether or not music wire under the typical tensions in a piano stretches in the long term, this is all I've found. ----------------------------------------------------------------------------------------------------------------------------------------- This is from Mechanics of Materials, by Larson & Cox, published by John Wiley and Sons, 1947 "When an elastic material, such as steel, is loaded at ordinary temperature, it deforms in proportion to load almost simultaneously with the loading. Thereafter, the load may apparently act on the material for an indefinitely long period without causing any further appreciable change in dimensions. Even if the material is stressed above it's elastic limit, after an immediate deformation there appears to be no further change in dimensions until there is some change in load." From Tool Engineers Handbook, by the American Society of Tool Engineers Handbook Committee, published by McGraw-Hill in 1949 "At room temperatures, creep is of no practical significance in steels, but does reach measurable proportions in such metals as lead, tin, and zinc." ------------------------------------------------------------------------------------------------------------------------------------------ That's it. I've asked a couple of mechanical engineers the same question, and they said that low temperature creep in steel is not something anyone allows for, as far as they know, and is generally ignored as a non event. In other words, there are no periodic tension adjustments made on suspension bridge cables as they stretch, and they aren't slowly dipping into the waters beneath. Ron N
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