Avery, Well, that's because we're piano tuners, and we think of tuning pins' and bushings' reaction to humidity. They're different from key balance holes. A hole in a piece of wood (not laminated) changes with humidity exactly like the plug of wood that used to be in the hole. So the hole grows a little larger, though not symmetrically, when the piece of wood swells up and gets bigger. With tuning pins, you have cross-laminated wood that can't move much, plus you have wood fibers within the hole compressed tightly against the pin. So those inside the hole surface fibers swell when the humidity is high, making the pin gets tighter. All it takes is one time prepping a piano under one condition, then seeing the piano again in the opposite, and this becomes quite apparent. Take it from Houston to Denver, and hoo boy, those key balance holes get tight! Don Mannino From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of Avery Todd Sent: Sunday, October 09, 2011 5:01 AM To: pianotech at ptg.org Subject: Re: [pianotech] Easing Balance Holes : Kawai KG-1E Don, What am I misunderstanding here? Shouldn't it be just the opposite, ie, freely drop in dry weather and barely slide during humid? If it barely slides during dry, it's going to tighten up more during humid and be too tight. Right? Straighten me up here if I'm wrong. Hmmm.. Avery Todd Houston, TX On Sat, Oct 8, 2011 at 4:38 PM, Don Mannino <donmannino at ca.rr.com> wrote: Paul, The ideal easing is for the key to slide down slowly, but keeping in mind the humidity is important. In variable climates like yours, during very dry weather ease it so that the key barely will slide back down the pin. During humid weather, it should fall freely. This method makes the keys with more lead weights slightly tighter. Don Mannino -----Original Message----- From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of Paul Milesi Sent: Saturday, October 08, 2011 1:00 PM To: PTG Pianotech List Subject: [pianotech] Easing Balance Holes : Kawai KG-1E I am working on a 1991 Kawai KG-1E (5'4") in a church. Among other things, I replaced key bushings. While easing keys, I realized that the balance pins are installed perfectly perpendicular to the rail, rather than angled back. Should this change my approach to easing the balance hole? I was taught to lift the front of the key anywhere from 1/4" to 1" while the back of the key rests on the back rail, and to ease for free fall of the key. It seems to me that on any piano, at some point lifting too far and easing to allow for a freely falling key will cause chucking (pulley key). In this particular case, does having the pins perpendicular require less, or no, lifting at the front, but rather lifting front and back of the key to check balance hole fit? Hoping Don Mannino might be watching.... Paul Milesi RPT Washington DC (202) 246-3136 <tel:%28202%29%20246-3136> Cell/Text paul at pmpiano.com http://www.pmpiano.com <http://www.pmpiano.com/> -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20111009/ec41defe/attachment-0004.htm>
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