---------------------- multipart/alternative attachment At 10:37 PM 01/21/2000 -0500, you wrote: >>John, I don't remember Duofulcrum keys ... can you tell me what brand >>that was? And how did the keys have two fulcrums? > >As you know, most balance rails are flat across the top with the punchings providing the pivot.. Heintzman figured that introducing two "peaks", or continuous quarter-rounds, one for the white and one for the black keys, would accelerate key movement.... thus, duofulcrom. Get it? of Theodore Heintzman. > John Lillico, RPT, >Oakville, Ontario, Canada Someone else picked up on that idea. Personally, I don't think they accelerate the keys enough to compensate for the amount of extra work involved to level the keys. Spot levelling is a real chore. One thing they do contribute to the lever system is to maintain the fulcrum close to the pin. On a flat punching the fulcrum moves towards the front of the punching as you depress the key. Regards, Jon Page, piano technician Harwich Port, Cape Cod, Mass. mailto:jonpage@mediaone.net ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/c0/46/fa/46/attachment.htm ---------------------- multipart/alternative attachment--
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