Even balance weight or even something else, that's thequestion.

[Bill Ballard]

At 9:28 PM +0200 4/22/03, Richard Brekne wrote:
>I thought that was where you were going. And in that case I dont see 
>how dynamic balance in this sense can be achieved in the piano 
>action at all, at least not with the stationary mass of the key 
>leads, hammers and for that matter all the wood in the action parts. 
>Dynamic balance in this sense is really a mathematical construct to 
>begin with, and is more or less the sum of an << infinite >> set of 
>discontinous points of static equalibrium, is it not ? Even the tire 
>example only uses the tires motion to identify a spot where static 
>imbalance is significant enough to be << noticed >> as it were.

I agree. Either you have to have a way of dynamically measuring the 
inertia in an action, or you simply have to trust the completeness of 
the mathematical model and adhere to the changes it suggests you 
make. With all of its assumptions, the mathematical looks more like a 
static piece of work, than dynamic. But neither of these are anything 
we'll be able to afford or which will fit in our daily tool box.

At 4:05 PM -0700 4/22/03, Phillip Ford wrote:
>They don't have much choice.  And most of them don't like change. 
>But if they were given a chance to live with some other setups I 
>wonder if they wouldn't end up preferring them.  (I suppose this is 
>a bit like the temperament discussions).
...snip...
>It would be interesting to have an action on which it was quick and 
>easy to change these various parameters and get feedback from 
>pianists as they tried it with different setups.  Another thing to 
>go on the list of things to do.

The only part of David Stanwood's current action set-up which is not 
quickly and easily variable is the FW (inertia). To a certain extent 
this can be mocked-up, temporarily gluing leads to the top of the 
key. You'd have to replaced the fallboard with a piece of Masonite, 
as pianists prefer to make judgements with all the panels on, and the 
actual fallboard would limit how much of the length of the key you 
could glue weights to.

If you can measure it, you can set it up initially, and you can 
correct it when it drifts.

Bill Ballard RPT
NH Chapter, P.T.G.

"I go, two plus like, three is pretty much totally five. Whatever"
     ...........The new math
+++++++++++++++++++++