Hi Ric, I think what he means, is if you add 3mm (for instance) to the bore of hammers at some point along your strike line, the bulk of the hammer's mass (the big felt part) is now further from the pivot point. This has to affect MOI. As my good friend Stan Kroeker suggests, when you move the weight up or down on an old metronome, it certainly seems to have a measurable (predictable) effect on the speed. The same would be true for curving the line by moving hammers further/closer to the center-pin. So, while I'm enjoying the exchange of good methods for measuring strike weight, sorting, thinning shanks etc., I'm struggling with the concept of sorting shanks over .1 gram difference, distributed who-knows-where along it's length, but moving a 4-10g hammer in/out by several mm and not accounting for it. (!?) If I've missed this in the discussion, please (anyone) feel free to "tune me in," either on, or off-list. I'm in favor of the pursuit, but just need to know that we are aware of and dealing with "all" the variables. BTW Ric, thanks for the spreadsheet, it's a good working tool! Best regards, Mark Cramer, Brandon University -----Original Message----- From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On Behalf Of Richard Brekne Sent: February 15, 2008 3:25 PM To: caut at ptg.org Subject: [CAUT] hammer line11 Now this is an interesting concept. How does altering the bore length to match string height variances move the mass farther out on the arc... and how does this in turn add up to a more serious problem then the at least two biggies I can see it corrects ? Cheers RicB So, if the strike line you set "by-ear" ends up being a little crooked, and uneven string height is the culprit, why not vary the bore-length? A wise and valued supplier who I turn to for pre-hungs when things get "bizzy," will not do this for me. His claim being that moving mass further in/out on the arc will have more detriment than anything I'm trying to correct.
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