overcentering justified?

[A440A@aol.com]

Bob writes: 
<< Going back to my original question about hammer bore distance affecting 
the performance of the action, it seems that you are leaning towards other 
causes of the slow repetition more than the change in bore distance and its impact 
on knuckle/jack/wippen center relationship.  

   There is a lot of interrelated cause and effect in an action.  When you 
change the bore distance, you are changing the starting position of the hammer 
shank, and if the knuckle is a different size, you have compounding factors.  
These dimensions are changing the event timing at escapement and slightly lower 
than drop, so, without having the action in front of me,  I can only draw 
some general conclusions/confusions. 
 
>>One puzzling thing is the comment about Roger Jolly's labeling of 
aftertouch as anathema to repetition since the key had to travel through it before 
things can reset.
Do you think that .050 aftertouch is beginning to be too much for that 
reason? >>

  Way too much.  If possible, get your dip and blow related so that you have 
no more than .035".   I have begun setting up Steinway actions with a usual 
.033" aftertouch and customers are very happy with the response.  I have concert 
actions out there with .025" and .040"  and they are considered to be playing 
very well.  
    I use the aftertouch priority method for several reasons, one of which is 
that a pianist is far more likely to notice, say, a .010" difference in 
aftertouch from one note to the next (which represents a 33% difference between it 
and another note) than they are to notice .010" difference in keydip, which is 
only a 4% difference between keys.   Another reason is that many notes a 
pianist plays do not start from the top of the keystroke, but rather, are played 
again before the key is fully released.  This makes any difference in keydip, 
per se, a moot point.   
Ed Foote RPT 
www.uk-piano.org/edfoote/
www.uk-piano.org/edfoote/well_tempered_piano.html
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