[pianotech] key position at rest

[Jon Page]

>...I see how you can trace backwards  with these specs to
>find the key height and key end height.

OK, now to confuse things a bit...

A few years ago, a dealer asked me to see what I could do with the high BW
on a S&S B since the in-house guy's only thought was to add more lead to
the already overly leaded keys.

I noticed there was two rather thick pieces of underfelt on the back rail.
This necessitated an inordinately thick amount of punchings on the balance
rail to maintain key height. But the key end felt height was 1 3/8".  And the
Magic Line was way too low, respectively.

I removed one of the layers of underfelt, removed enough balance rail punchings
to maintain key height and the BW dropped (something about action elevations).
The ML fell into line. But now the end felt was lower now.

I didn't think to point out that new end felt may be needed (when I 
returned the action)
to maintain damper timing. I assumed that with the improved touch, it 
would be obvious
to upgrade the end felt. I went back some time later and the 'house 
tech' reinserted
the underfelt to get the end felt up, piled on the balance rail 
punchings and the BW
skyrocketted again.  He didn't have an understanding of elevations 
and touchweight.
It would have been easier to install thicker end felt to maintain damper timing
rather than sacrificing touchweight. Some people are clueless and 
prefer it that way,
or it's just that they don't know what they don't know.

Now when I do something like this, I automatically reset the end felt 
height, and it paid off
recently on a S&S B because the 'amended' end felt was too thick. 
Here, again, not having
the piano, just the action; I went on what I knew/hoped/assumed was 
the situation of damper
lever height, lucked out.

What is needed is a spec height for the bottom of the rear of the key.
M&H has that: 15/16" to the bottom of the key.

Regards,

Jon Page
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