This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. ---------------------- multipart/mixed attachment Eliot, Regarding action center friction, the purpose in using a gram gauge to measure friction is to insure that the friction is even throughout the set. The spring type gauge works fine for this. Swing testing does not lend itself to evening the friction throughout the scale, because the heavier bass hammers swing longer than the treble hammers. Hammer flanges in grands should be pinned with 2 to 6 grams friction, depending on the firmness of the cloth, the weight of the hammers, and the relative humidity in the air on the day they are pinned. Measure friction by pushing the spring tip of the gauge on the flange near the screw hole. Once you establish a good recentering technique there is no need to measure every flange - the technique should give even results with only a quick finger test to make sure you didn't snag the cloth when putting the pin in. A good tolerance is +- 1/2 gram throughout a set. +- 1 gram is easier to attain, but that gives a maximum - minimum range of 2 grams, which is a little much for a really nice action. Some actions will perform well with lower friction, but this is risky in repinning as they may loosen up a little with use. More the 6 grams will make the action feel heavy and slow in most pianos. Soft spongy cloth often requires higher friction to make sure that the shank isn't wobbling as you play. If you can firm up the cloth by shrink fitting it first then pinning with a larger pin, you can improve the feel of this type of action tremendously. Don't worry about filing the hammers damaging the centers - unless you are being really rough with the hammers you should not damage the centers. if you raise them up on a voicing block to support the tails then strip sand them you should not be torquing the shanks enough to hurt the centers. Don Mannino RPT ---------------------- multipart/mixed attachment A non-text attachment was scrubbed... Name: not available Type: application/ms-tnef Size: 3968 bytes Desc: not available Url : https://www.moypiano.com/ptg/pianotech.php/attachments/9c/c1/52/00/attachment.bin ---------------------- multipart/mixed attachment--
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