Science and Metrology

[stanwood]

I'd like to respond to many of your postings but I'm a little pushed for
time today.
So I feel compelled to state my general views regarding the subject of
metrology.

To know a piano action is to know the following:

1. How much weight is thrown into the string?
2. How is the weight thrown?
3. How is the weight balanced?
4. How much friction in the system

The present "Down Weight" system does not give any information about these
quantities.

I have found that these parameters may be quantified by measuring:

1. Strike Weight
2. Strike Ratio
3. Balance Weight
4. Friction weight

These four quantities are a function of:

Up weight
Down weight
Front weight
Strike Weight

Compared to the regulation sequence of a grand piano action, the
calculations for finding these quantities are relitively simple.  This is
all new and unfamilar to most of you and I remember the first time I
attemped to regulate a grand action.  I hadn't gotten the big picture yet
and the task seemed endless and impossible.  Now it is second nature.

I will be publishing a formal article on the subjectof the New Metrology as
soon as I have time to write it.  In the mean time I find the discussion
that we are having on the subject to be most valuable. If any of you are
going to Dearborn for the Annual Institute you might want to look at my
class discriptions which will give a very complete instruction on the
subject of how and why pianos feel the way they do:

 http://www.tiac.net/users/stanwood/inst96.htm

I really have to get to work.

Talk to you all soon.

David C. Stanwood