Don, I hadn't realized there _were_ factories that burnished for final fit. I'm guessing you'll say there is at least one, and its name starts with K ;-) According to my limited knowledge of manufacture, many manufacturers simply insert the pin in the bushing and use a shrinking/sizing solution, while premium manufacturers would have an intermediate step where they would insert a sizing wire (string a bunch of newly bushed flanges on one), and dip all into solution, then let dry and remove and pin parts together. Come to think of it, maybe I've answered my own question. Is that sizing wire also the burnisher? Removing it being the burnishing process (assuming it's long enough)? From what I heard Eric Schandall say, this year in Dallas and last in Chicago, Steinway's process also includes dipping/saturating in emralon solution as a last step. He seemed to be saying this in the context of presenting improvements in quality control, and implying that the emralon was quite important in final fit. That it conformed to the pin. He did talk about the possibility of gaining friction somehow over time (without speculating as to why, just saying it did happen), and suggested the solution of applying methanol to dissolve the emralon, hence causing it to re-size to the pins. (And said nothing else would work, as water/alcohol wouldn't be absorbed, and Protek wouldn't have any affect). I had always had the impression previously that the "Teflon II" bushing was not essentially different from any other wool felt bushing as it might behave with Protek saturating the cloth. But after listening to Eric, I am not so sure. Among other things, I wonder if it is hygroscopically contrary, just like the original teflon bushing was/is. IOW, the bushing is hygrocopically inactive (won't absorb moisture, so won't swell or shrink), but the wood is. So in low humidity, as the hole in the wood is smaller, the bushing is tighter, and vice versa. Just a thought, not based on experience. Regards, Fred Sturm University of New Mexico --On Friday, October 3, 2003 8:20 AM -0700 Don Mannino <dmannino@kawaius.com> wrote: > List, > snip, Factories which burnish the bushing for > final fit very rarely will have tightening problems. >snip< > Don Mannino > > _______________________________________________ > caut list info: https://www.moypiano.com/resources/#archives
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