---------------------- multipart/alternative attachment This is interesting data... interesting in light of what renner says about hornbeam (that it's stiffer). Are there grain orientation differences between the samples (assuming that is a consequential variable)? vince James Ellis <claviers@nxs.net> wrote: N.Y. Steinway, pre-1920, maple Knuckle stock: H = 0.255 W = 0.472 Round shank, tapered 0.243 to 0.200 at 4.75 from center. Strike weight: 1.3 gram Vertical bend: 0.059" N.Y. Steinway, modern, maple Knuckle stock: H = 0.260 W = 0.475 Round shank, tapered 0.260 to 0.220 at 4.75 from center. Strike weight: 1.7 gram Vertical bend: 0.035" Renner octagonal, hornbeam Knuckle stock: H = 0.240 W = 465 Shank, octagonal, uniform, no taper: 0.240 Strike weight 1.6 gram Vertical bend: 0.061" Thinned treble shank, make unknown, wood unknown. Knuckle stock: H = 0.240 W = 0.465 Shank, oval, uniform, no taper: 0.235 x 0.1875 Strike weight: 1.7 gram Vertical bend: 0.065" I considered measureng the torsion stiffness as well, but that would have required another setup, and considerably more time. The results speak for themselves. If we are interested in stiffness - vs - weight, the round tapered shank is definitely superior to the non-tapered octagonal shaft. Little is gained by the octagonal shape, and much stiffness is lost by not having a larger cross section near the knuckle. We are dealing here with a lever, not a structural beam. Whatever you might or might not say about Steinway, New York, they obviously have the right idea here. The shank is stiff where it needs to be stiff, and light where it needs to be light. That design make good sense to me. Sincerely, Jim Ellis _______________________________________________ caut list info: https://www.moypiano.com/resources/#archives --------------------------------- Do you Yahoo!? Free Pop-Up Blocker - Get it now ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/caut.php/attachments/d6/4d/71/19/attachment.htm ---------------------- multipart/alternative attachment--
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