Hello John,
I fully agree with you regarding the "grams" statements. Perhaps the best
we can do using this measure alone is to make the friction uniform, or well
graduated from end to end.
However, swings may actually be a useful and very efficient method of
measurement. I am thinking that the heavier hammers can perhaps benefit
from slightly higher friction than the light ones. Heavy hammers need
better (tighter) bearings to maintain good alignment under heavy loads, and
the higher friction (within normal limits) also imparts some control to the
player when the inertia of the lower hammers becomes noticeable. While
swings don't translate into MKS units of measure, they can in their own way
act as a unit that makes sense to piano technicians.
Ideally, I think we would probaby like to know how compliant the bearing is
to the twisting of the shank and also how much torque it takes to turn the
shank around the flange. But for know, I am reasonably happy with the swing
test for simultaneous measurement of these two parameters.
Vladan
>As to "swings", hammer number 1 will swing more than hammer No. 50
>for a given friction, and so on.
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