I thought I'd mention an interesting and useful material I've found for shimming the frontrail holes in the keys of a McCobb fortepiano (Graf copy) here. This instrument is 15 years or more old, and the keys produced considerable clacking noise because of excessive play on the front pins. I should mention that the keys have what I suppose might be termed "key shoes" (as opposed to recessed "plates") made of hardwood, U-shaped, and glued to the bottoms of the keys around the frontrail hole. I assume these were installed in the hope that the hole would stay the proper size for a longer time, but these are also ultimately what caused the problem of clacking. Because once they've worn enough to allow for any play whatsoever then there can be plenty of noise introduced. In a recital here a couple of years ago the noise could be heard clearly from the audience. So my problem was to find a thin enough material to use as a shim, or "bushing", in order to eliminate the play between the key and pin. There was very little play, really, so at first I tried using superglue, and it worked - but the difficulty of trying to get any kind of consistency of thickness, having to file away the excess, etc. made it rather tedious. What did work well, however, was linen tape (any art frame shop has it, used for mounting art works to matts, etc.) - it's gum backing glues it quite strongly in place. I cut small pieces and glued a piece as a shim on one side of the key hole ( the tape is only .006" thick, and still I had to file away with little pieces of emery board as files in order to allow for enough play that the keys weren't binding on the pins!) In other words, only about .003" of play was enough (because of the hardwood shoes) to allow for lots of noise in these keys. I don't know how long these shims will last, but I'm hoping that because they have some cloth content that they'll hang in there for awhile. An sort of unusual and specialized problem, I know, but for others of you who work on fortepianos, perhaps this is a useful material to keep in mind - has anyone else out there used it? It might have other purposes - shimming hammer flanges on modern pianos? although it might stick TOO well for that purpose. Once it's on and dried it's pretty tough to get it off. Allen Wright, RPT Oberlin Conservatory
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