[CAUT] tight balancier

[rwest1 at unl.edu]

Wim,

My only suggestion is: Don't go to extremes.  The part you want to  
work on is called a "repetition" lever not a backchecking lever.   
Having a slightly tighter center can help hold the hammer high after  
let off and help the rep lever do what it's supposed to do.  But too  
much friction requires a stiffer spring which actually works to keep  
the hammer tail away from the back check and will result in making  
your problems worse.  I remember some teflon era Steinways that had  
very tight rep lever centers.  Good backchecking on a mf blow was  
almost impossible.  Of course there was also the problem of short  
hammer tails in Steinways of that era.

Getting backckecks to work right has always bedeviled me, so I  
sympathize.  Do a search of the 20 Year Journal CD's and read the  
articles about backchecks, just to be sure you're not missing  
anything.  I find the angles of the hammer tail and backcheck  
surface, and the geometry (height of the backcheck at rest in  
relation to the hammer tail, for example) need to be perfect in some  
pianos.  There's no wiggle room in the regulation or geometry.  If I  
were to cheat, I would reduce the spring tension in the bass to  
eliminate the bouncy feel of a big hammer being pushed up by a rep  
lever.  Yes, the jack needs to reset, but not as fast as in the tenor  
and treble.  Power is more important in the bass than repetition  
speed.  These are just the kinds of compromises that some pianos  
require.

Richard West


On Nov 10, 2006, at 4:43 PM, Willem Blees wrote:

> Quoting RicB <ricb at pianostemmer.no>:
>
>>
>> This said... Skolnik covers a lot of good ground on this thread in a
>>
>> short space.  Wims problem .... Wim, seems to me you have more or
>> less
>> eliminated the balancier centerpin tightness and the repetition
>> tension
>> from the field of potential sources of your problem.  Strikes me as
>> time
>> to look for other sources. David listed up quite a few classics.
>>
>> Cheers
>> RicB
>
> Ric
>
> I have done just about eveything David mentioned to solve
> my "bobbling" problem. If you recall, I just found out about the
> balancier centerpin solution at the seminar a couple of weeks ago. So
> this is basically my "last resort".
>
> As I said, I got a bunch of balanciers up to 6 grams. Now I will go
> for more resistance, when I can find a couple of hours in the hall.
>
> Wim
>
>
>
>>
>>
>>     David writes:
>>     << The ability of the hammers to be held in
>>     check is affected by:
>>     <SINP>
>>     jack position at rest - too far forward will leave jack too close
>> to
>>     knuckle after let-off, either allowing descending knuckle to
>> bound on
>>     jack top, or the back radius of the knuckle will rub or
>> otherwise
>>     push jack out of the way, stealing energy from the descending
>> hammer
>>     that might prevent it from overcoming rep spring.>>
>>
>>     I don't know that I understand this.  I believe that the jack
>>     position at
>>     rest, if moved farther under the knuckle, will simply cause the
>> jack
>>     to begin
>>     moving earlier in the keystroke, (for a given let-off).  Once
>> the
>>     jack is off the
>>     spoon, it doesn't matter where it started.
>>         It is helpful to place the action in check, then adjust the
>>     capstan so
>>     that the jack is equidistant between the knuckle and the stop
>> pad.
>>     This is your
>>     optimum blow distance for that particular let-off and dip.
>> Changing
>>     the
>>     beginning jack position won't have any effect on this.
>>     Regards,
>>
>>
>>
>>     Ed Foote RPT
>>     http://www.uk-piano.org/edfoote/index.html
>>     www.uk-piano.org/edfoote/well_tempered_piano.html
>>
>
>
> Willem Blees, RPT
> Piano Tuner/Technician
> School of Music
> University of Alabama
> Tuscaloosa, AL USA