A small magnet will help determine the difference between iron and aluminum. Aluminum repels a magnet and iron attracts. Use a small magnet. It is possible to evaluate a scale in about an hour to determine what was there. I do not have the confidence in the old ways you do because I have seen poorly scaled pianos being manufactured now. After all, we can do more in a few minutes with a computer than the old timers could do in a month. The other problem, which got me started in rescaling in the first place, is that the string makers do not follow the original scale, even when they have the scale stick!!! Too often in the past I would get a replacement set of strings that sounded worse than the originals did. I finally traced this down to the fact that the winders would shorten the copper at the agraffe end by 3/4" to 1" which changes the inharmonicity, radically. Inharmonicity increases by the four power of the unwound ends. By designing my own scale, or even using the original scale, I can get what I want by sending the string winder a set of specifications instead of samples, a pattern or a make and model. Use your software and if you have questions give one of us a call. Newton nhunt@jagat.com
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