[pianotech] action ratio

[David Love]

Those comparisons would be useful.  I think there's no question but that we
regulate to suit the piano, ultimately.  While we may think we have targets
of x blow and y dip, in reality we regulate based on what's required and
often end up with something other than what we planned or even think we
have.  However, I believe that the demands of the particular piano are
inextricably linked to the action ratio. 

David Love
www.davidlovepianos.com


-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of Ron Nossaman
Sent: Wednesday, August 29, 2012 7:09 AM
To: pianotech at ptg.org
Subject: Re: [pianotech] action ratio

On 8/29/2012 8:47 AM, David Love wrote:
> Not to beat a dead horse but FWIW one thing I do notice, with my 
> action model anyway, is that the jack movement (and key movement for 
> that
> matter) from the point of jack tender contact with the let-off button 
> is about 2.5 - 3 mm which, on my model, translates to about .040" key 
> travel after the point of escapement.  So if "aftertouch", at least in 
> this formula, is based on travel after contact with the let-off button 
> when the jack starts to move horizontally rather than vertically, then 
> the output of my design chart seems consistent with real world results.

Good observation. I'd be curious to eventually see at least a small
compilation of comparisons between feel adjust - measure, and measure - feel
judge to see how definable our individual "windage" actually is.
Ron N