<html> Del, Bill, et al, At 07:44 AM 12/21/99 -0800, you wrote: <blockquote type=cite cite>----- Original Message ----- From: David ilvedson <ilvey@jps.net> To: <caut@ptg.org> Sent: Monday, December 20, 1999 8:33 AM Subject: Re:teflon bushings > I have to admit it has been awhile since I reamed a teflon > bushing, but I remember being taught to score (roll between > two bastard files) a centerpin the same size as the one in the > bushing.  You used this in a pin vise.  Anyone else use this > method? > > David I. ------------------------------------------------ This might be good enough for the occasional emergency, but if you want good results you'll go with specialized reamers.  This method did more to destroy the chances of the Teflon bushing's success than anything else.</blockquote> I fully concur.  In fairness, however, this method was first introduced by Freddie Drasche in the early years (read: "dark ages") of servicing teflon. At that time, even if the appropriate tools were available/in use at the factory, they were not available to outside technicians.  Since these parts (and their associated actions) were perfect in every way when they left the factory (and, therefore, never required servicing), it was not deemed necessary to provide instructions for their service.  Freddie, of course, realized the magnitude of the problem, and came up with the centerpin method - which he presented and demonstrated all over.  (Well, I suppose that the method may not have been original to Freddie, but, it was, pretty darned amazing disaster control, all things considered.) It has always seemed to me that teflon never really got a proper start. The original (smaller, and unribbed) bushings were too small to be stable. The later ones, while of better design, still suffered from poor machining of the maple parts, a bad rap from the earlier ones, and simply appalling technical support from the factory.  In spite of all of the above, however, there really is no reason that these parts cannot be reliable and provide very long service - perhaps, if well maintained, long than their felt-bushed relatives.  First, while one should get the factory technical bulletin (can't remember the number), Del's post is the best method I have seen written out.  He mentions (and, I believe Joel does as well) paying careful attention to the fit of the bushing in the appropriate part.  I do not remember if Del posted to this list or to pianotech - if pianotech, his method should be in the archives - if on this list, I am not sure, and I do not remember if this list has a searchable archive or digested form.  The parallel reamers are a very small amount of money as compared with the speed and accuracy of the job they allow one to do.  Just as indispensable as the combination reamer/burnisher sets available for servicing felt-bushed parts. Best to all, Horace </html>