[CAUT] Steinway repetition center pin height

[Richard Brekne]

Hi all

I have to admit this still seems a bit strange. Not that I doubt anyone 
mind you... but one thing nearly all replies have alluded to is a 
situation where the shank is resting on the cushion.... and at the same 
time resulting in a condition where the jack can not get under the 
knuckle if it was not already under there to begin with.

This speaks to me of two problems. First... the jack is supposed to be 
under the knuckle well before the the shank even gets close to the rest 
position after play.  If it doesnt.. then either the rep lever spring is 
too weak, or the center may be to tight.. or the jack is regulated too 
far out... similar things. The rep lever is supposed to lift the hammer 
via the knuckle up to a position where the jack can slip under as soon 
as (nearly immediatly after) the key is released.  Second... if resting 
on the cushion to begin with... then either the rep lever spring is to 
weak (again)... or the whippen is simply regulated too low. A low 
whippen wouldnt cause this problem... quite the opposite really... it 
would solve it by introducing an artificial sort of lost motion.

All this said... I've run into actions where something like this seems 
to happen to individual keys.  Not to the point of action failure.. but 
to the point where getting a stable hammer (rest) line is virtually 
impossible.  I've always solved the problem with friction control 
measures... replacing worn parts... and securing a good enough 
regulation with appropriate spring strength.

If the cushion height forces the hammer to rest too high... this should 
basically just result in an uncomfortably shallow dip.  If its too 
low... a dip which would be too deep.... yes ?  no ?  Id like to hear 
from Bob Hohf on this one... seems like his action heights article 
perspective would be valuable here.

Cheers
RicB



        Ric writes:

        I have not thought of this has being related to relative
        positions of the balancier and hammershank centers tho. And I am
        still a bit foggy on how these can contribute to this condition.


        hmm,  I may have stepped on a semantics snake, here. I didn't
    mean to say
    that the relative positions of these two *contribute* to the
    problem, but
    rather,  illustrate the condition, ie, when the Knuckle is so low
    that the action
    cannot reset.  One major cause, I believe, is that in the capsized
    state, the
    hammershank is resting on the cushion so its weight isn't helping
    the key
    return. this leaves only the spring to overcome the FW and return
    the key to its
    at rest position, which it is not designed to do.  


        On the surface of it... it would seem that as long as you
        regulate with in reasonable correspondence to specs... all should
        work reasonably well.


    I  agree, however, the normal in a Steinway is that the specs are all
    over the place, (generally owing to excessively high or low  plate
    height).  This
    is why the brand allows the creative regulator to excell.  These
    actions
    respond to regulating according to principles rather that pre-set
    figures.  I have
    increased the height of the rest cushions to overcome the capsizing
    problem.
    It is not only much easier than raising the cleats, it doens't upset
    the
    hammerflange pin to string relationship, (though there is often much
    to be improved
    in this regard if the pinblock is not too thick.)

    Regards,

    Over recent years, Steinway has begun to increase their allowable 
    keydip to
    accomodate longer knuckle geometry, but that is another discussion. 

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