Isaac asks: >So the basis of your argument is that steel does not creep with time >under tension ? Yes. In the context of piano strings under normal working tensions and conditions, although I have not done experiments that would back that statement, nor have I seen any published data that relate to pianos per se. However, under normal working loads and room temperature, creep of structural materials such as steel is generally considered negligible. Creep is basically a thermally driven process, so it usually only becomes an issue for steel at high temperatures, e.g. in turbines, jet engines etc. >The method proposed use absolutely the opposite, it want to produce >that creep in an accelerated way. Not necessarily. It is only the assumed rationale the a creep mechanism is involved. There is a difference between creep strain [time dependent response to constant stress below the yield point] and plastic strain in response to [sudden] applied stress exceeding the yield point. The latter is essentially instantaneous. >I am waiting for other answers from wire makers and factories, I don't >understand your position at this moment. I don't really have a 'position'. I'm just offering a possible explanation for what is going on, one that doesn't make the assumption that creep strain is relevant to the instability of newly-strung piano wires. >So for the moment, the Stephen's concept makes sense to me - then, in >regard of the different type of wire he propose, I have not enough >clear data to talk about, the few colleagues who wished to try them >did not obtained enough basic information's also, so we are waiting >for it, and this is planned for September. I'm a little confused here Isaac. You mean 'Stephen Paulello's concept'? or my concept [which one]? and do you mean the wire which I'm currently making or some wire of Stephen Paulello is planned for September? Stephen B -- Stephen Birkett Fortepianos Authentic Reproductions of 18th and 19th Century Pianos 464 Winchester Drive Waterloo, Ontario Canada N2T 1K5 tel: 519-885-2228 mailto: sbirkett[at]real.uwaterloo.ca http://real.uwaterloo.ca/~sbirkett
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