In a message dated 1/18/01 11:21:46 PM Central Standard Time, jgrassi@silverlink.net writes: << Good evening, List, While zoning out on a tuning today I realized I had been staring at the nose bolts on this Petrof Grand for quite some time. That was when I realized that I don't know very much about them....their true purpose, when they are tight enough, how are they supposed to be tightened. I know some of you have all sorts of information on these rather respectable size screws and I'm just dying to hear from you. jeannie >> Nose bolts are there to keep the plate from exploding. The bolt up from the soundboard has a ledge on which the plate sits. The nut on top is tightened to keep the plate sitting on that ledge. When the plate is put in, before strings are put on, the bolt is turned so that the plate and the ledge are together, without raising the plate. The nut should also not push the plate down. Either one of those will bend the plate, which is not good. Contrary to what some technicians think, down bearing cannot be adjusted with the nose bolt. Lowering the plate, by lowering the nose bolt, and tightening the nut, is not going to give the piano more down bearing. All that will do is put the plate under tension, and it might crack. Willem
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