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<DIV><FONT face=Arial size=2>As a mechanical engineer, I concur with Ron.
John's cite of the high tension electrical wires makes it clear that they are
being tensioned beyond yield strength, which is why the article suggests heat
treating the wire (which increases yield strength). Yield strength is the
point where the wire would plastically deform (stretch) which is less than
ultimate strength (breaking stress). Therefore, you -could- stretch piano
wire, but you would be pulling it above its yield strength. This would be
more likely with more ductile wire which has a yield strength
appreciably lower than ultimate. With a more modern piano wire, yield
strength is closer to ultimate.</FONT></DIV>
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size=2>
Mike</FONT> </DIV></BODY></HTML>