One thing it does suggest (assuming no measurement error) is that setting balance weight by taking up and down weight measurements and adjusting lead weights accordingly has its limitations. The claims of some touch designers that their actions are balanced to the .1 grams is obviously limited by the ability to determine accurately the actual UW and DW in a given system (when does the key really start to go down and when does it actually come up) and the potential for variations in friction to skew the data and thus the resulting action taken to achieve those uniform balance weights. Working from the other direction, a calculated front weight curve based on a given strike weight curve and a constant action ratio, is also limited by the actual accurate executions of the contributing levers themselves to achieve a precise action ratio through the scale. While attempting to set a very precise standard will likely yield better results than targeting a less precise standard, it is somewhat unclear as to where the point of diminishing returns falls. Just a thought. David Love www.davidlovepianos.com I just happened to be finishing repinning a set of hammers, so took the liberty of measuring UW/DW at two different levels of gram resistance in the flange. FWIW: Note Hammer Flange Friction (g) DW UW Hammer Flange Friction (g) DW UW 3 1 56 34 4 60 32 4 1 55 28 4 59 26 6 1 55 35 4 59 33 8 1 54 32 3 58 31 9 0 54 34 4 57 32 11 1 54 32 4 56 31 -- William R. Monroe -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/caut.php/attachments/20101204/3db4e860/attachment.htm>
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