Hi Newton, 60% of the strings tension when it is up to full tension in the piano. We all know that the string will stretch as we increase the tension on the string, by as much as 10 millimetre or more. Whilst this is happening the copper windings theoretically should be parting by a '.' amount. Now if the string when tuned has 80 kilo of tension and has stretched 10mm then : If the string was wound at 40 kilo tension with a stretch of 5mm then the '.' gap would be wider than if the string was wound at 48 kilo (60%) with a stretch of perhaps 3mm. I would think that a string wound at a higher tension would require less twist than the string wound at the lower tension. But there must be a point where if you have too much tension (say 80 kilo) that the copper wire would be crushed when the tension is released and the string shrinks. Possibly the right tension is that one that causes the string to not hang straight. ? Hope you understand what I am trying to say. Regards Tony > You are getting into some of the arcane aspects of string making. > > First, some string winders "straighten" the wire as it comes off the coils. > Some do not, thinking that curve is important to the quality of their strings. > The copper, which is not all the springy, will not impart much of a twist to the > string when hanging loose. > > 60% of what? Your question, as stated, is not clear. You do not want to exceed > 65% of the breaking point of that size of wire. This does not happen often but > it can on big pianos and on the tiny ones with real heavy wraps. > > Newton Tony Caught Darwin Australia caute@optusnet.com.au --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.361 / Virus Database: 199 - Release Date: 08/05/02
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