Tuning Pin torque

[Geoffrey Pollard]

List,

Does anyone have good information on an acceptable range of tuning pin
torque for good tuning stability. My  interest is in trying to set an
'objective'  borderline for assessing grey market pianos and so-called
remanufactured pianos when our Association members do pre-purchase
inspections. We also have some support from the retailers association to
set some guidelines for presentation of second hand instruments.

I would be grateful for answers to all or any of the following:

1.  What is an acceptable range for tuning pin torque consistent with good
tuning stability?

2.  Are there any significant variables to take into account?
      ( I'm wondering here whether bushed/non-bushed/open wrest planks may
differ significantly. )

3. How is it measured, ie. what tool and what technique?
    ( I seem to remember hearing that the measurement must be taken while
turning the pin anti-clockwise or pitch
      lowering.)

Geoffrey Pollard
Sydney Conservatorium of Music
Sydney, Australia.



Geoffrey Pollard
Piano Technician
Sydney Conservatorium of Music