I suspect loose coils. Not so much on the vertical but the wrap around the pin. Separated coils do not inand of themselves contribute to instability but slackness in the wrap does. recently, I had a Samick which was 'squirrelly' tuning wise. I gripped the coils with parallel pliers and rotated counter-clockwise and the pitch dropped on each string betwqeen 60c and a minor 3rd. It is very stable now. This is my new normal procedure for many ~20 y/o piano which come thru the shop. To relieve the strain on my grip, I fashioned a pair of wire bending pliers to do this, photo att. -- Regards, Jon Page -------------- next part -------------- A non-text attachment was scrubbed... Name: coil tool1.jpg Type: image/jpeg Size: 209908 bytes Desc: not available URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20130107/6a8e8215/attachment-0002.jpg> -------------- next part -------------- A non-text attachment was scrubbed... Name: coil tool4.jpg Type: image/jpeg Size: 46897 bytes Desc: not available URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20130107/6a8e8215/attachment-0003.jpg>
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