[CAUT] steinway upright regluation problem

[Edward Sambell]

Hi Fred,

I forgot to mention that the wippens in taller pianos are  larger than those in 
consoles and thus are a bit heavier. Your point on taking care of friction and 
related things is well taken. My assumption was concerned with that done and the 
problem still existing. My aim is to set a diagnostic procedure. Incidentally, I 
once attended the Europiano  Conference, and engineers from Schimmel said that 
the jack spring strength should be about 30 grams. This is measured with a 
Correx or similar force gauge between the jack heel and let-off button There 
should also be a minimal amount of lost motion between the jack and butt.I am 
sure I do not need to remind anyone of that.Jeremy also mentioned hammer weight; 
this is of less significance in an upright than a grand. As you say, adding a 
little lead to the back of the key is the cure.

Regards, Ted




________________________________
From: Fred Sturm <fssturm at unm.edu>
To: caut at ptg.org
Sent: Sat, September 25, 2010 1:43:04 PM
Subject: Re: [CAUT] steinway upright regluation problem


On Sep 25, 2010, at 11:28 AM, Edward Sambell wrote:

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.
Hi Ted,
I think you have analyzed it well, and it is a common problem. It is exacerbated 
by wippen cushion dimpling and friction between the cushion and the capstan, 
which should be addressed first. It can sometimes be alleviated by increasing 
jack spring tension, which will mean the jack is pushing against the butt 
leather and assisting the reset a little more. But I usually just add lead to 
the backs of the keys, as the most efficient way to solve the problem. It 
usually only takes a single smallish lead fairly close to the capstan, and when 
there are only a few offenders, I sometimes have just glued it on top of the 
key. I have a Wurlitzer console player (1960s-70s Aeolian mechanism) with that 
same problem, and so getting the keys out is a major operation. Hence, I have 
glued maybe 15 - 20 leads to the tops of keys, with no problems over a period of 
a few years. A fairly large amount of titebond so it forms a collar, and they 
stay fine. Another option is jiffy leads, which can be cut in two and screwed on 
(a whole jiffy lead is a lot of overkill).

Regards,
Fred Sturm
fssturm at unm.edu

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