In measuring and reporting tuning pin torques what is the normal assumption about the contribution of the string to the measurement? This will provide about 35in.lb helping of hindering tuning pin torque depending on the turning direction during the measurement. Typical values are often mentioned, eg. "loose pins are when torque is <50in.lb" "ideal tuning pin torque is around 100-150 in.lb range", ">200in/lb torque is tight pins" and so on, without saying if these are intended to be true torque (i.e. no string), or clockwise vs counterclockwise with a strung pin at tension. The latter will vary +/-35in/lb or so [for a typical full tension string]. I suspect the reported pin torque values probably refer to counterclockwise and strung pins, since it's more likely this is how they would be measured [although not when re-pinning a pinblock of course]. So a torque of say "50in.lb" woulld actually be a true torque of around 85in.lb with just the pin. But I'm guessing this is the intent of the reported numbers. On the same subject, I'd be interested to know what hole sizes are typically used by our various dramatis personae here, say for reference 2/0 pins. But tell us your pinblock material as well for obvious reasons so comparison is meaningful. Stephen -- Dr Stephen Birkett, Associate Professor Department of Systems Design Engineering University of Waterloo, Waterloo ON Canada N2L 3G1 Director, Waterloo Piano Systems Group Associate Member, Piano Technician's Guild E3 Room 3158 tel: 519-888-4567 Ext. 3792 fax: 519-746-4791 PianoTech Lab Room E3-3160 Ext. 7115 mailto: sbirkett[at]real.uwaterloo.ca http://real.uwaterloo.ca/~sbirkett
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