[CAUT] steinway upright regluation problem

[Edward Sambell]

Hi Jeremy,

This is a problem I have never seen mentioned, in print or anywhere else, yet is 
not that uncommon. Sometimes it is so severe that some keys will not return to 
rest at all.It is mostly confined to consoles, but I have seen it in a Steinway 
1098. The reason is that the keys are too front heavy, or, as in a piano made 
here in Canada, the capstans have been installed too far forward. The latter can 
be determined from the wear mark on the wippen cloth. In the past I moved the 
capstans on many of these. 

A sure test is to sit at the piano and depress both pedals. This ensures that 
the weight of the wippens alone is on the keys. Next, depress all the keys, 
using both hands in clusters. The weight of the wippens should return all the 
keys all the way. Back weighting the keys will increase the toughweight of 
course, but I usually found that the butt springs are too strong. They should 
not be horizontal when slipped out o the butt notch, but in theory about 45 deg 
,so weakening them will compensate for the increased touchweight. Should the 
capstans have to be moved the touchweight increases too, and in addition, the 
keydip might need to be increased, though a better and simpler solution is to 
reduce the hammer blow distance. Otherwise there will be bobbling hammers.
The reason this happens in consoles lies in the key design; if we compare the 
keys from a taller piano, we see that there is usually an added block at the key 
end to carry a capstan screw or a dowel. In the smaller piano the key is 
possibly cut down at the back in order to reduce height, and moreover, it does 
not have the added block. Not surprisingly these keys are poorly balanced, and 
in the case of the piano I mentioned, the maker stubbornly refused to weight 
their keys, preferring to drill the capstan screws in the wrong place. I know 
they sent out their techs to fix complaints, and they would try to fix the 
problem by increasing the strength of the butt springs. Didn't work. If a wippen 
alone will not return the key, the jack will not reset under the butt. 


Hope this helps, Ted Sambell






________________________________
From: J H <jlhservice at gmail.com>
To: caut at ptg.org
Sent: Sat, September 25, 2010 10:40:15 AM
Subject: [CAUT] steinway upright regluation problem


Hi all - I recently tuned a small S&S console from the 40's (the little short 
ones, somewhat decorative case).  The hammers/keys returned to rest very very 
slowly when the damper pedal was being used, and it was noticeable even without 
the pedal engaged.  Other than newer hammers, it's all original.  The hammers 
seemed a little oversized for the piano.  So, I have checked everything: hammer 
flange center pins and return springs, wippen flange centerpin, jack centerpin 
and springs, capstans for buildup/residue, keybushings, key balance hole, 
dampers, everything.  No problems with sluggishness anywhere.  Each part of the 
action, the hammer, wippen, and keystick operates fine independently.  The 
hammer/wippen actions operate just fine when you remove the key and push up on 
the capstan pad.  The only problem is when you introduce the key.  It really 
seems like things are binding up at the capstan pads.  So, could wear and tear 
cause the cap/pads to bunch up and throw off the regulation geometry?  The 
cap/pads are pretty worn and "dimpled".  Could the larger replacement hammers 
change the way an upright hammer returns to rest?  Did I miss something?  The 
customer probably won't even notice this but it's bothering me that I couldn't 
figure it out.
 
Thanks!
Jeremy

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