Try this ,
Home made Mason Hamlin tuning tool. (Refer to my screw stringer posting
of Sept 5 2003)
1'4' drive -Sears T-handle,6"extension 1/4"deep 12 point socket wooden tool
handle-(rosewood optional)
CA 'D all components together -
https://www.moypiano.com/ptg/pianotech.php/attachments/38/57/f6/91/P1010070.JPG
Tom Driscoll rpt
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