Del, David, Ken, Jim, List: Based on David's post, we might solve the problem if we all moved to the Bay area! Even in southern California we get climatic extremes - especially the "Santa Ana" winds - and their milder and more sustained high pressure systems which keep the air between 5% and 30%RH. For whatever reasons, the teflon actions I run across have plenty of clicks and oval bushings. I think that the rolled pin technique continues to survive throughout the country - endorsed by the Steinway manual - and somehow there needs to be a journal article or tech post which gently lays this, and the other myths, to rest - and provides us all with a reference, complete with a discussion of the problematic service techniques. One of the key elements to Del's post is that we actually cut the teflon with a many-fluted reamer - no filing or burnishing. The bushing surface should be smoothly cut. I have NOT been satisfied with the results I obtained with my reamers - and Del clearly explained why - mine are single fluted! I obtained them back in 1990 from Johnson Carbide (Steinway referred me to Johnson Carbide). Any Journal discussion might include the source of Del's 6 fluted reamers (probably Johnson...) If I remember right, I was trying to get double-fluted reamers at the time - and Del's post refers to any reamer less than 4 flutes as inadequate. My Steinway Technical Reference manual also refers to a four-fluted reamer. But it has a few things which might be changed: the graduation of the reamers should be .0005", not .005" (two graduations per .001"). Also, it considers rolling a centerpin in a file acceptable. Is this because Steinway knows that many technicians will not spend the $ for a set of reamers, and a centerpin rolled on a file is better than tapered tools? I still have questions about the durability of the teflon vs. cloth, but what seems to have become clear is that there continues to be vast misunderstanding about service techniques and performance/durability expectations regarding teflon bushings - and Del's post helps to get us out of the mud. I hope that what Del has said gets into the Journal prominently. Even if we may not all completely agree on teflon bushings, his contribution could significantly improve the service level of those teflon-bushed actions. Thanks, Del. Bill Shull In a message dated 99-03-08 11:44:08 EST, you write: << As I recall clicking problems were often caused by the factory reaming one side of a bushing, i.e. pushing the pin out enough to ream the empty side then pushing the pin back in. The swing or gram test was fine because one side was too loose and the other tight=click down the road. I have used Don's reamers with some success but teflon is slow to react compared to cloth. I believe you are suppose to roll center pins between files and put them in pin vises? Here in >>
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