Hello Philip > If the piano's in mint condition why do you want to restring it? Well, the instrument had not been played since before WWII, and was 100 cents low. When I started rising the pitch, 3 every 5 strings broke. I decided to restring. > Where can we find the Stephen Paulello papers that you refer to? Isaac knows better about that. I included Paulello's strings infos in my reply to RicB. > If the modern wire has a higher breaking strength, then why are you > concerned? Are you worried about the yield point? Are you worried that > you will have a lower percentage of breaking strength on the wire and that > this will affect the tone? Are you worried that the different strengths > may indicate different material stiffness? Yes. But in this case, the measures lead to the conclusion that the german wire from 1870 has the same breaking strength as the modern german wire. My first post was not so clear, I made it (hopefully) less unclear in my reply to Ric. Indeed, my concern is about sound. Scaling evaluation on this piano showed that the plain wire was tensed at between 50% and 60% of the breaking strength (that is : the supposed breaking strength as calculated following Dave Roberts formulas from his "Calculating technician" series of articles in the late 70's). This seems to be a high tension, foreseen that the formulas apply to this strings. But if the formulas refer to wire that breaks at an average 2000 N/mm², like modern wire should do (following this time the data from Stephen Paulello), then, either my scaling evaluation is false, or my 1500 N/mm² breaking strength measure was inaccurate by a generous 25% relative error (huge). What do you think ? Stéphane Collin
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