Jim, The graphite, if present, was most likely put there to improve the performance at the factory. It does not cause a sluggish center, nor does it stop sluggishness from happening. The idea is to reduce the friction level while giving a firm, controlled fit in the bushing. I am not fond of graphite in the bushing, because it actually increases the startup friction, even though it lowers the moving friction. Teflon works better for action centers in this regard. So repinning will still most likely eliminate the sluggishness, and a little graphite remaining should not present any problems. Don Mannino ----- Original Message ----- From: jim ialeggio To: pianotech at ptg.org Sent: Wednesday, April 01, 2009 5:15 AM Subject: [pianotech] graphite and center pins? A current thread mentions repinning as the solution to sluggish or sticking centers which have the tell-tale black spot indicating applied graphite. I don't understand how this would be a long term solution. Yes, the pin has been changed, maybe some felt has been removed with a broach, but the crud is still in the bushing. My interest here regards a long term rather than a triage fix. Jim -- grandpianosolutions.com Shirley, MA (978) 425-9026 -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech_ptg.org/attachments/20090401/140b1c0d/attachment.html>
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