> >Eric, >I'm confused. Seems to me that weakening the springs would increase the >chances of bobbling rather than decrease. An old Mason & Risch vertical >player (referred to in my other post) has these small butt mounted springs >which hook onto a cord that attaches to the brass rail through a hole just >below the butt plate. A few of these springs were broken, and not having >wire of a small enough diameter to match what was there, I had to replace >them with the smallest diameter rail mounted type springs cut and bent to >shape. The result was that the only notes that could be regulated with a >reasonably close let-off (1/8") were those with the heavier springs. (These >were repairs carried out in the customer's home. If I had the action in the >shop, I'd want to replace all the springs.) It appeared that, on this piano >at least, the lighter the springs, the more likely they'd bobble. Pinning >was free but not sloppy. > >Regards, > >Aaron Bousel >Ormstown, QC Canada >abousel@rocler.qc.ca Aaron, I found on the Korean instruments, the spring kept the jack and butt in contact way too much. In fact, there was no "breathing room" for the jack to escape around those little ridges in the buckskin and "bbbubbing!". By loosening them just enough to facilitate hammer return, it allowed the jack to escape and the butt to be caught by its catcher- thus stopping all movement. These weren't my ideas unfortunately. Brian DeTar was in three weeks ago and offered some suggestions on bobbling upright hammers. He is probably more able to describe and illustrate this phenomenon than I. (I DO try though!) Eric Leatha, RPT Portland, OR tunrboy@teleport.com "The Buddha, the Godhead, is just as at home in the circuits of a computer or the action of piano as on the top of a mountain or the petals of a Lotus flower." -Robert Persig (freely interpreted by undersigned)
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