Ed, At 07:27 PM 8/25/2004, you wrote: > ><< I was under the impression that one of the problems with teflon was wood > >swelling and squeezing the bushing thus tightening the flange... is this > >another urban legend? >> > >Not really. The wood distorts in response to humidity changes. > If the hole was round when the wood is dry, it is oval when the wood >absorbs more moisture,(wood changes far more across the grain than with >it). If >the hole is round when the wood is damp, it becomes oval when the wood dries >out! Yes...which is why the method you described earlier (an epoxy dip) works so well. Thanks for mentioning that, by the way. It was on my list and got lost someplace. > Teflon bushings require so little compression to give the proper friction >that any distortion that causes loss of round will allow noise. The smaller >teflon used in the earliest actions would distort and stay that way. I >recently repinned the damper action of a 1962 M that used cloth in the >action, but >teflon in the damper assembly! I repinned it because it was too tight to >allow >proper damping. It had never been worked on before, Go figure... Teflon bushings were introduced over time in different models in different places. I think that they specifically went after the Ds first (starting in 1959). Then, it is almost as if they were using up the parts that had been manufactured pre-teflon on a per-model basis...does that make sense? It would certainly account for what you describe; and jibes with a number of instruments I have seen from that general period. Best. Horace
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