Fred, I don't disagree with any of the comments regarding guage and scaling changes in harpsichord service. I would add to the discussion this hyphothesis. The thinner (finer) the wire the more fragile and even miniscule kinking, bending, moisture induced rust will compromize the integrity of the spool. In dealing with a bundle of (harpsichord guage) wire that breaks during restring process it is common that the wire has some form of contamination or introduction of mishandling. More often than not I myself am the culprit and pay the price of my inattention proper handling. Minimizing kinks is especially critical in the yellow and rose wires even thought they are heavier guage. Humbly respectful of the wire gods. Gerry Cousins West Chester University of PA From: fssturm at unm.edu To: caut at ptg.org Date: Fri, 4 Dec 2009 08:06:28 -0700 Subject: Re: [CAUT] Sperrhake Harpsichord wire On Dec 4, 2009, at 5:43 AM, DCyr141833 at aol.com wrote: The break point percentage of a given length of music wire remains the same no matter what diameter that music wire is. So going to the next size smaller, or larger, will not cause it to break more or less. Break point percentage is affected by wire size, and composition. So, if you can't make the speaking length longer, or shorter, you should look to use a wire of stronger materials. I know this is counter-intuitive, which is why I bring it up from time to time. Think of it this way. There is a reason we go from thinner to thicker wire going down a scale. In simple terms, when we go to a wider diameter, what happens is the tension goes up. For a given note (length and pitch), a thicker gauge will be at a higher tension to achieve that same pitch than a thinner one. The intuitive thing to do when a wire breaks, and when the same size breaks again, is to reach for a thicker, "stronger" wire. And it almost never works (if it does, there was something else happening). Any note on any piano can be strung with #13 wire and it won't break (all right, it has to be a normal piano). Won't sound good, but it won't break. Any wire on a piano can be replaced with a thinner one and it won't break. Think about it. Try it. It's a question of thickness, which is really mass in the equations. The extra mass slows down the vibration of the string, meaning higher tension is needed to speed them up. Like with wrapped strings. Add some wrap, and you will slow the vibration rate. To speed it up, you need to raise tension. Same thing with thicker wire, but you don't notice the increase in mass as readily. Regards, Fred Sturm University of New Mexico fssturm at unm.edu -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/caut.php/attachments/20091204/98142946/attachment-0001.htm>
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