I have just been watching this thread, too. The whole subject is new to me and fascinating. I have, like Norman, done a fair amount of reed organ work. This last bit gave me a thought. Is it possible that thinning the sides of the shank would decrease mass and thus raise the pitch, but have little effect on stiffness, since the bending stress on a shank is mainly in the vertical plane, but maybe thinning the top or bottom would decrease stiffness and lower the pitch? I haven't tried this. Regards, Ken Z. On 2/22/08 9:25 AM, "Ron Nossaman" <rnossaman at cox.net> wrote: > >> Chris & all >> >> I do know that to lower the pitch on a reed organ reed you scrape >> material from the bass end of the reed making the mass of the end of the >> tongue heavier in relation to the overall reed and the pitch goes down. >> I have never tried it on a hammer shank but I can see where the same >> principle would apply. >> >> Norman Cantrell > > Hi Norman, > In the organ reed, scraping the tip of the reed removes mass, > raising pitch. Scraping the base end of the reed decreases > stiffness, lowering pitch. > > Resonant frequency in anything is determined by a combination > of stiffness and mass. In the case of hammer shanks, it would > appear from the reported results that the loss of mass > realized in thinning has a greater affect on "doink" pitch > than the loss of stiffness. > > I don't tune shanks, so I wasn't aware of this. I would have > expected the shank pitch to drop. Interesting. > Ron N -- Ken Zahringer, RPT University of Missouri School of Music
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