A piano that keeps slipping that much over that much time has something major loose somewhere. Even a loosely strung tuning pin doesn't slip that much. Still, it's possible that the piano didn't have much of a tuning history prior to it's departure from the factory. I'd check for movement ........ the plate will lift if it's not secured well so check all the perimeter bolts and make sure there aren't maybe a few that are stripped out ....... rare but possible. Look for lifting or plate distortion all the way around the rim. The nose bolts should be tight and check for a crack in the plate at those points ......... the plate failures I've seen have all happened around the area where the struts meet the tuning pin webbing area. Check where the pin block meets the cabinet ........ from inside the action cavity look up at the junction ......... bass and treble. There shouldn't be a gap there. If the plate is distorting due to lack of anchoring, downbearing will be affected. A simple sewing thread stretched across the bridge, duplicating the path of the string will show if you have positive or negative downbearing. Check the crown of the soundboard. I don't expect a soundboard has enough crown in it to cause a piano to drop 100 cents, especially in the treble but it's easy enough to check ............. a thread once again strectched between the ribs tells all. The shim in the horn. Make sure it's still there. If there's a adjustment bolt, make sure it's tight. Just some ideas to check that are easily enough done. Lar -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech.php/attachments/20090614/9cc6cc70/attachment.htm>
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