---------------------- multipart/mixed attachment One could mic the breadth of the knuckles and group them accordingly but probably the main objective would be to press them into the slots with a caul to aspire to more consistent results (jpg attch'd). Then a further measurement of knuckle height could refine the shank groupings. On a new set of shanks, I sort first by shank SW sorting those to sub-groups of knuckle height. The knuckle_caul.jpg which is attached is the first prototype, made from mahogany. Consistent results were not achieved because the wood compressed as the procedure progressed. My next one would be made from HMD plastic. One machined of metal would be cost prohibitive for my purposes. Here's a tool waiting to be produced... Joe, ... Bill, ... anyone... I have used the caul to compress the knuckle to conform to a tolerance but have not followed up on measuring after a few years. I maintain a .010"/.25mm window of tolerance for knuckle height with the bulk in-the-middle (say ~.640") and hi's (.645") & lo's (.635") off to their respective sides. (Shank height does not vary enough to be a consideration). By grouping the knuckle heights, a smoother regulation is attained; one item evident of this is a straighter let-off button alignment. Just one of the plethora of hair-splitting, nit-picking details which consumes our work hours. I'm tired just thinking about it. Regards, Jon Page, piano technician Harwich Port, Cape Cod, Mass. mailto:jonpage@comcast.net ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ---------------------- multipart/mixed attachment A non-text attachment was scrubbed... Name: Knuckle_caul.jpg Type: image/jpeg Size: 33049 bytes Desc: not available Url : https://www.moypiano.com/ptg/pianotech.php/attachments/b5/0e/0d/75/Knuckle_caul.jpg ---------------------- multipart/mixed attachment--
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