Richard Brekne wrote: > I understood that it was generally agreed on (several years back as a matter of > fact) that graphite was found to be a definant no no in centerpin bushings. > Something about crystaline structure of graphite, some reaction to warming up after > a bit of playing causeing the freez up you mention. Yes. But Renner still uses it. And the last I checked was unwilling to leave it out. I suspect that they will maintain this position until several of the German manufacturers request a change. > I regularly clean out this as > best I can and work a little teflon powder in the bushings instead. > > I have used teflon powder in this way for about 6 years now and find no adverse > reactions whatsoever. I have 30 or 40 pianos I visit yearly that I have done this > to so I have been able to keep track of the results. One thing I notice is that its > much much "safer" to go with 4 swings tightness then without teflon, and definately > safer as compared to using graphite. We also have used Teflon to lube action centers. But it's well nigh impossible to get that graphite out of there. How much time can you afford to throw at a problem that shouldn't be there in the first place. I would love to see Renner switch to rubbing or spraying a bit of Teflon powder into their bushing cloth. I think it would do their action center consistency a world of good. Might cost a bit more, however. Graphite is cheap, Teflon is not. > Suprises me that folks are still using graphite in centers Surprises us as well. Del
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