Glue wicking into flange bushing cloth is a source of squeeks. The CA glue isn't causing this problem? Because it is so diluted? David I. ----- Original message ----------------------------------------> From: Robin Hufford <hufford1@airmail.net> To: Pianotech <pianotech@ptg.org> Received: Sat, 11 Dec 2004 13:29:39 -0600 Subject: Re: Rebushing centers/mystery center pinning >Hello Richard, Don and Barbara, >A few more comments interposed. > First, I did try today the use of alcohol as a wetting agent; it >was useless as it served only to accelerate the reaction and >immediately harden the mixture as Don Rose predicted it would. Also, >while applying it to a piece of bushing cloth as Barbara considered >doing it was obvious that there really was no need for a wetting agent >as it disappeared almost instantaneously upon being dripped onto the >cloth. There was no discernible puddling or lag time. Again, this was >a Don predicated. Two for two. It may be however, that the >penetrabilty of this mixture may be different in a bushed flange whether >the pressure in the bushing may have to be taken into account. The >obvious effect of this stuff was to stiffen and harden slightly the >cloth as I intended. >Richard Brekne wrote: >> Hi again Robin, a couple comments below >> >> Robin Hufford wrote: >> >>> Hello Richard, >>> ..... However, simply because the claim is made that the bushing >>> is hard doesn't mean, in my experience, they will be, perhaps yes, >>> perhaps no, perhaps sometimes and one probably will not know when >>> until perplexing difficulties arise. One can take the >>> hammershank and flange in hand and hold the flange tightly while >>> trying to wiggle the shank in a way so that the pin can be made to >>> move back and forth in the bushing and watch this motion. A soft >>> bushing will show more motion of the pin in the bushing and that is >>> a serious problem as it has a really detrimental effect on the sound. >> >> >> Herein lies at least one tentative test for Barbaras flanges and it >> would be nice to hear what she observes in this regard. Up to this >> point I've been taking for granted that the bushings in question were >> as previously described. >> >> >>> Sometimes, as I Barbara and I both have experienced, repining is only >>> a temporary improvement; in the face of such a frustrating experience >>> I tried the method I described. It appears, as I said, at least for >>> the moment to have both worked at the time of use in stabilizing the >>> friction and wobble and led to no discernible subsequent pining >>> problem. But, again, its purpose was to deal with an overly soft >>> bushing. >> >> >> I have to admit I've never tried the kind of solution you describe >> above, being hesitant to apply any chemicals at all to either hammers >> or bushings. Too many unsatisfactory experiences for my part. > In general, I thoroughly agree: A clean pin, of the right alloy, >with a proper woven felt cloth, properly densified, I think, can be >shown to have worked for generations reliably and can continue to be >expected to do so. Why fiddle around with anything else? A lesson, in >my opinion, these various companies should take to heart. But they >don't and they put out, generally for frivolous reasons, the kinds of >products of which we are taking note of here. But, in this case, here >was a problem in need of a solution, which, in the case of my use of the >technique, appears to have worked. >> What I have found works very well is to work a good deal of teflon >> powder into the bushing and burnish very agressively followed by a >> rather tight pinning. Generally if I do have a problem afterwareds it >> goes in the opposite direction and I need to loosen things up a bit. >> Perhaps I might give your suggestion a try tho on some spares I have. >> Never thought of using CA in this context before. >> >> >>> If I were Barbara in this situation I would find two or three really >>> weak sounding notes from the middle and low treble and change nothing >>> else but the density of their bushings with the mixture, or take the >>> time to use water with alcohol, and judge from the results. I think >>> is absurd even to have to do this lesser task by necessity but even >>> more so when it is necessary to take the time to rebush parts for >>> which one has already paid good money to have acceptable bushings >>> come along with the rest of the order. I'll have to climb down off >>> my soapbox here before I get myself really worked up! >>> Regards, Robin Hufford >> >> >> Agreed, should be an un-needed operation for high quality parts. But >> then, assuming these are the new NY Steinway parts... we (I at least) >> dont know really what these are like from the get go. That said... the >> whole concept of bushings with such low friction does not appeal to me >> in the first place. >It doesn't to me either: I am not sure it is even a valid technical >idea and it seems this idea may only be a stop-gap attempt to deal with >the problems of geometry, excessive mass and friction which one sees in >the present production. >> RicB >> _______________________________________________ >> pianotech list info: https://www.moypiano.com/resources/#archives >> >_______________________________________________ >pianotech list info: https://www.moypiano.com/resources/#archives
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