At 6:49 PM -0500 10/8/01, Ron Nossaman wrote:
>Yep, and as the friction changes in the action through wear or technical
>intervention, the DW will also change, though nothing has been done to the
>leads. Then when someone comes along to get it working again and measures
>FW, they find these wild differences from key to key.
The business of action balancing sure is alot muddier if we choose a
measurement (say, DW with an eye towards wayward UWs) which bundles
mass and friction together. As problems to be alleviated, they
involve separate troubleshooting and remedy. Thus, DW as an action
resistance measurement (DW) is not very useful in showing were our
work lies, as neither it nor its companion UW are the slightest bit
interested in revealing whether we have a friction or a mass problem.
I switched to Balance Weight many years ago and have not looked back.
Admittedly, BW is based on the assumption that a lever train with 0.0
friction would have identical DW and UW, and that as friction occurs,
it can be assumed to push the DW and UW in opposite directions by
equal amounts. Not a bad one on the face of it. But an assumption for
which there may be no proof, especially since DW, UW and the
derivative BW are static measurements.
Still, I haven't looked back. I see action resistance troubleshooting
as a series of forks. Is it a friction or a mass problem? If it's a
mass problem, is it because of extra mass at the hammer end of the
lever train, or at the key end, or is it a leverage problem which is
aggressively amplifying the current hammer weight. It sure fits in my
toolbox better than a system of dynamic measurements and analysis,
although I have great admiration for Stephen Birkett's ability to
build such a system.
Bill Ballard RPT
NH Chapter, P.T.G.
"Talking about music is like dancing about architecture"
...........Steve Martin
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