Tom writes: >rebushed in the customary way, using hot hide >glue, Renner bushing cloth, Spurlock sizing and key bushing cauls, >After 6 months to a year, the key bushings, usually but not always >front bushings, have deteriorated to the point of having excessive >side to side motion. This usually occurs in the middle of the >keyboard and is found on both naturals and sharps. >Upon examining the front guide pins, we discover a hard red substance >on one side or the other, usually on the left (bass) side of the pin, >which acts like sandpaper and gradually wears away the key bushing >cloth. I assume that this could be a combination of glue and bushing >cloth dust. >Any ideas about what might be going on? Are you using the cauls to achieve the sizing of the felt to the pins? If so, you may be impregnating the felt with a lot of glue, which means that there is effectively little to cushion left,(sorta like ending up with extremely thin cloth and a lot of glue behind it. This felt will wear away rather quickly, and then the glue that was impregnated in it will begin to collect on the keypin. This has been one drawback to using thicker cloth than required and having the cauls mash it into a thick bed of glue. It doesn't leave a very resilient pad in the remaining felt dimension. The fix, as I have seen it, is to use only enough glue to hold the proper size cloth in place. This vintage Steinway often has overly large mortises,(as well as that dreaded "white glue"), and the choice of key bushing cloth is a problem. I got around this on several that are at our school by gluing in (with Titebond) very thin shims of veneer so that I could use standard Steinway bushing cloth. Just my thoughts about what it could be, since I did see this problem once before. REgards, Ed Foote RPT
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