Barbara, I believe these are called Thayer (spelling?) shanks or thayer knuckles. John Hartman RPT John Hartman Pianos [link redacted at request of site owner - Jul 25, 2015] Rebuilding Steinway and Mason & Hamlin Grand Pianos Since 1979 Piano Technicians Journal Journal Illustrator/Contributing Editor [link redacted at request of site owner - Jul 25, 2015] John Hartman The Universal, How-to, Hands-on Illustrator [link redacted at request of site owner - Jul 25, 2015]
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