On November 14, Joe Goss wrote that a 3/32 hex shaft is as strong as a 1/4 round shaft (talking about hammer shanks). Today, I asked how he arrived at that conclusion. Today Joe answered. Joe, in your answer, you compared a 1/4 round shank to a 1/4 hex shank. That's obvious. But that's not what you said. You originally said a 3/32 hex shank is as string as a 1/4 round shank. 3/32 = 0.09375. That's less than 1/8 inch. I never saw any hammer shank that small, even in an antique piano, but that's what you wrote. I went back and checked your statement twice. So, I assune you meant 3/16, not 3/32, but that won't work either. I laid out a few sample Renner shanks, but they aren't hex. They are octagonal, and they are certainly much larger than any 3/32 inch, and definitely larger than any 3/16 inch for that matter, no matter where you measure them. Since this issue has been raised, I'm going to go back and make a few stress/strain measurements on some different types of shanks, and just see which bends more than what. I'll get back with the results in a few days. Let's all try to avoid making wild guesses. OK? Sincerely, Jim Ellis
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