---------------------- multipart/alternative attachment Richard Brekne wrote: > - There is seemingly a conflict between a desire to have as little lead as > possible as opposed to a desire to place any lead as close to the center pin as > possible. Have had a couple hours to look at Stephens PDF link on this subject and see that it very nicely describes what I was after in the above observation. http:/real.uwaterloo.ca/~sbirkett/inertia.pdf Comparing the two first graphs ploting acceleration against force input for three configurations of keys, shows that though more lead does indeed generally increase inertia, lead placed closer to the center decreases it. The unbalanced (unleaded ?) key stick provides a sort of baseline on which what is refered to as a soff / hard (play) breakpoint must occur regardless of whether lead is used or not. Soft in this sense I think more equates with the word "easy" or "light" and hard equates to "difficult" or "heavy" (correct if wrong Stephen). Installing lead in general yeilds a less steep acceleration gradient, yet at the same time the closer to the balance rail pin the lead is installed, the farther out on this baseline that breakpoint occurs which steepens the gradient. Essentially concentration of key mass closer to the center of the key reduces the difference between a the three configurations, while at the same time expanding the domain of soft play. In theory, I suppose if you could concentrate enough balancing mass close enough to the center of the key, the difference between the balanced, partially balanced, and unbalanced keys would become null, with a nearly exclusively "soft" play characteristic. Said another way, the farther out on the red line (no balancing line) the breakpoint is placed, the more alike in terms of what the graph illustrates the three cases given become. This would seem to indicate to me, that the placement of lead primarily determines the location of of the breakpoint and thereby the division between hard and soft zones, and the amount of lead used detemines the degree of balancing and thereby the degree of divergence from the no balanced configuration for any given breakpoint. I hope its ok that I included a low res reproduction of the general case graph for reference. And Stephen, if I have misunderstood things please correct as neccessary. Thanks. RicB [Image] -- Richard Brekne RPT, N.P.T.F. UiB, Bergen, Norway mailto:rbrekne@broadpark.no http://home.broadpark.no/~rbrekne/ricmain.html ---------------------- multipart/alternative attachment --------------2CBCAFDB7491FE42016E4FDA An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/87/b9/e3/1a/attachment.htm --------------2CBCAFDB7491FE42016E4FDA A non-text attachment was scrubbed... Name: C:\\DOCUME~1\\RICHAR~1\\LOCALS~1\\Temp\\nsmailNP.jpeg Type: image/jpeg Size: 19190 bytes Desc: not available Url : https://www.moypiano.com/ptg/pianotech.php/attachments/ba/a3/fa/41/nsmailNP.jpeg --------------2CBCAFDB7491FE42016E4FDA-- ---------------------- multipart/alternative attachment--
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