Hi John. I once had a university professor test for me the breaking strength of a sample 1mm diameter Ršslau wire and a sample of 1mm diameter original Bechstein wire from a 1871 piano, see how they compare. Both samples had the same breaking strength, that is sure. Now the guy reported me the breaking strength was 1500 N/mm?, which is much less than what Ršslau claims. The guy told me that the way you clamp the wire in the testing machine has a tremendous effect on the measurements results. Now, what are we measuring ? And what do the results mean ? How would you do the measurement of Young's modulus ? Best regards. StŽphane Collin. As to the coefficient of elasticity of the wire (Young's modulus), rather than go by unreliable generalized values it is best to measure it. It is quite simple to find out which of these two figures is more correct. The more precise you want your figure the more trouble you'll need to take with your apparatus. JD
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