> From: David Boyce <David at piano.plus.com> > Date: March 12, 2011 8:24:47 PM EST > Yesterday I tried hammer filing using a small Dremel-type tool for the first time. Hitherto, I've always used home-made sanding paddles. The Dremel filed ones look good. You must have a steady hand. I've done plenty of scrap hammers with a Dremel, but I never go consistent enough to trust it on a real action; it's so easy to Dremel off too much felt, and so hard to glue it back on. <G> I'll leave the finest and most critical cuts to the gemcutters and mohels (ouch!), and stick to slower sandpaper. Yours look good though. > I am attaching two pairs of before-and-after pics. One from hand filing, and yesterday's with the little drill. In the hand-filed photo, I was taught to start the filing further towards the tail than you did; I start at least before the widest point, and often before or at the staple. The reason for this is that if you start after the widest point (if you start closer to the crown), you are effectively increasing the hammer radius at the crown, thus flattening the hammer crown. This is illustrated by the exaggerated photo below. If you filed off the part outside the dashed circle, the crown would be flatter and the hammer-string contact area would be greater. Of course, this is much exaggerated as compared to your photo, but I have seen plenty of poorly filed hammers that are not much better than my exaggeration. I'm not suggesting that you would ever do that, but I thought I'd point it out since it jumped out at me. I try to take off a whole layer of the hammer felt whenever possible. I don't have any advice about getting rid of the discolored felt, other than starting near the staple as I've suggested. However, my suggestion was made for functional rather than cosmetic reasons. Joe DeFazio Pittsburgh P.S. - Totally useless bonus points for any (and all) who can name the brand of piano that the pictured hammer came from (look closely).... -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20110313/3040c816/attachment.htm> -------------- next part -------------- A non-text attachment was scrubbed... Name: HammerRadius.jpeg Type: image/jpg Size: 29223 bytes Desc: not available URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20110313/3040c816/attachment.jpg>
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