Center pin friction, yet again.

[A440A@aol.com]

David writes:

<<  is there any consensus 
regarding the ultimate effects of the difference between "0 grams, without 
any sideplay", and whatever measurement might provide the "traditional" 5-7 
swings (of the hammer)? >>

Greetings, 
   NO, there is no consensus!!!  All of us seem to have variations on a theme 
inre hammerflange friction.  Reactionary trolls in their darkened shop 
corners don't usually do it the way of the factory production line.  

Some of the melodies I have heard played in the technical counterpoints we 
call "discussions" : 
1.  Zero friction is better, it improves the touch response.
2.  The firmer the better;a mechanical damping allows a stronger spring and 
key response to be controlled.
3.  Just enough to prevent sideplay is all that is needed, (continuo to # 1, 
above)
4.  Firm enough to focus the tone and no more.  
5.  Whatever it is, as long as it is consistent, its OK, ( this is more of a 
cadenza for the individualist)

    My own procedure was that taught by Bill Garlick, and it has stood me in 
good stead through all these years.  It is humidity influenced.  I swing the 
hammers to test friction, I count each pass through the nadir as a swing, i.e., 
if I let the hammer go from horizontal, and it swings out and back, that is 
two swings. 
     The bass hammers are heavier, so I pin them swing 6 times, the middle 
will swing 5, the top will go 4. 
If the weather is very dry, I let everybody gain 2 swings, if the conditions 
are very humid, I may reduce all by 1 swing. 
     Since all reaming will lose some tension after sufficient playing, I 
leave those bushings that I have had to, for one reason or another, ream a lot, a 
little tighter. (sometimes one bushing is fine, but the other is verrrry 
loose, causing me to ream the tight one a lot. It will lose tension more than the 
other, so I leave a little firmer fit in anticipation). 
  I live amid my rebuilds, so I get to see how this system fares with time, 
especially in the school.  It generally leaves me what I want, but 
occasionally, I find a repinned flange has loosened up a lot from where I left it.  I 
learn from this, because I pencil the pin size under the hammer shank boss, and 
the date.  The drastic loosening almost always comes from situations where I had 
to ream a lot of felt to equalize the two sides. (see above).  Leaving extra 
firmness on these heavily reamed bushings minimizes this problem, but not 
always.  
        The tone is affected by tension when the tension gets too low.  With 
practice, you can learn to hear pinning looseness.  It is not unlike a broken 
hammer joint, just a little more subtle.  I have had one situation where I had 
to repin the hammer line on one day, and return to regulate the next. The 
owner, (a professional classical pianist), remarked how much better the piano 
felt and sounded after I did nothing but repin!  The acoustical connection of the 
hammer/shank/string/flange/action rail is certainly a factor in how the 
transient impact forces are defined upon hammer contact with the string.  I liken 
it to the control of sound any employs by changing their hold on the sticks.  
An artistic percussionist can dramatically alter the sound by how tightly or 
loosely they grip the mallets or sticks.  (This is a Canadian concept that was 
worth the price of a convention several years ago).  
     The later model Steinways felt is trickier. They say to use alcohol for 
the actions that tighten up, but my results with this have been way too 
inconsistent to accept.  If too tight, I ream slightly looser than I would like, 
since the felt seems to recover and re-swell more than others.  If too loose, the 
next size up will often be perfect. If not, then the least about of reaming I 
do, the better. 
     The factories don't seem to ream anymore.  They use a liquid solution to 
size the bushings around smaller pins, then take them out and replace with a 
larger size.  It is quick, cheap, and inconsistent.  It may leave results good 
enough to get the instrument out the door, but for fine work, it leaves much 
to be desired.  I have not found any substitute for individual attention to 
the bushings.  
    Consistency is paramount, and if you want a well finished action in both 
tone and touch, you Jolly well better check them all!  (:)}}
Regards,

Ed Foote RPT 
http://www.uk-piano.org/edfoote/index.html
www.uk-piano.org/edfoote/well_tempered_piano.html