The hammer hits the string when the keystroke is at halfway point?? Something really strange is going on. Only one key involved or all? If only one or two check the hammer butt spring. It might be that the spring is not there where it should be and produces that extra force you are talking about. I had that problem once and the reason was that the spring had left the cord that is supposed to hold the spring. Now when I am writing this I can´t figure out where the spring had gone, but it was the problem. Because it´s a Chinese piano it might be that many springs are involved due to cheap design and production. Gregor ------------------------------------------ piano technician - tuner - dealer Münster, Germany www.weldert.de Date: Tue, 18 Aug 2009 10:01:51 -0500 From: IFixPianos at yahoo.com To: pianotech at ptg.org Subject: Re: [pianotech] double-striking hammers on chinese uprights On Tue, Aug 18, 2009 at 9:07 AM, Britney Kirk <bkirk at summerhaysmusic.com> wrote: What causes a hammer to double-strike on an upright? When I play the key, it feels like there is an extra force at the beginning of the keystroke. When the keystroke is at the halfway point, the hammer has already hit the string and started to come back. When I have finished my keystroke, the hammer has returned and hit the string once more. I have tried re-pinning the hammer flange and doing a finer regulation. The only thing that seems to help-- but not actually solving the problem, and creating other problems-- is setting let-off extremely far from the string. Any ideas? Assuming the regulation is correct and the dip isn't too shallow or the blow distance too long and the hammer check is at 10.5mm or therabouts. 2 things come to mind, early damper lift and spongy or soft hammer return springs. Mike -- I intend to live forever. So far, so good. Steven Wright Michael Magness Magness Piano Service 608-786-4404 www.IFixPianos.com email mike at ifixpianos.com _________________________________________________________________ http://redirect.gimas.net/?n=M0908axHotmail2 Erster! Sommerfotos mit Hotmail versenden - 70% schneller! -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech.php/attachments/20090818/89ba8735/attachment.htm>
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