[CAUT] CAF

[Richard Brekne]

Hi Chris and Andrew

Ok... now these two posts put the whole thing in a little different 
light for me... and I can relate to these posts really well.  
Essentially... one is pointing out that whilst one can in most, even 
extreme cases <<regulate ones way out>> of the problem, (at least as far 
as the lock up issue is concerned) one in these same extreme cases 
causes  in the process other issues that are perhaps just as if not 
nearly unacceptable.... i.e. extremes of key dip, hammer blow... etc.  
In addition the point Andrew makes about drop screws simply not being 
able to high enough to do their job drove the point home for me.  I have 
usually solved this kind of thing by thining the drop screw cushion on 
the whippen rep lever.... but I will look closer at this buisness of 
whippen center height visa vi hammer center hight much closer in the 
coming months. 

Thanks one and all for the enlightening perspectives.  Please continue 
throwing out your thoughts on this issue.  I am all ears at this point.

Cheers
RicB


    While I do agree with most of the remedies recently presented for
    CAF there is the possiblility of reducing hammer blow too much and
    reducing power by trying to "regulate it out." Sometimes, either
    because upon investigation you find that the centerpin height
    relationships to the string height have been tampered with, or
    possibly set incorrectly originally(?!) you may want to raise or
    lower the back mounting block (usually raise). If you do this you
    can reduce or eliminate the tendency to lock up on fast shallow
    repetition but you should rotate the entire stack around the hammer
    center pin by lowering (in most cases) or raising the front mounting
    block. This is the usual orientation for the stack in Steinways,
    higher in back. If you just raise or lower the rear block thereby
    raising the wippen (repetition support flange,ala Steinway) center
    you will throw the hammer center forward or backward causing among
    other issues centering problems. Depending on the degree to which
    one does this you may have to plug and redrill the screw holes in
    the mounting blocks although usually there is enough "play" in the
    cleat holes. This is the indicated "fix" in MM's fore finishing
    notes and Bob Marinelli and I have done this many times. It is
    important to note that pinning the balancier up is also very
    important as others have noted and I wouldn't want to move the stack
    around without having good friciton there first. But there can be
    other reasons to move the stack in this way not least of which is
    that someone else has tampered with the arrangement or that is was
    set incorrectly originally (?!) as I have said.
    I would like to know what procedure you use Ed F. for replacing 88
    cushions because installing 4 shims and making a few swipes with a
    plane on the mounting blocks seems like alot less work to me. But
    then I 've been so wrong for so long it sometimes seems like right
    to me.
    Chris Solliday

    Ric,
    When Steinway New York builds their grands with the string-plane well
    above spec. and does nothing to accommodate that with the action this
    can be a very real problem.  This is a problem that is plaguing
    technicians in some very big school systems.

    A D at one of the schools I service was over-striking by about 3/16"
    when brand new.    Some hammer shaping later and it is probably
    closer to 1/4".  If the springs were a little weaker I'd be dealing
    with occasional catastrophic failure.  As it is, the shanks are well
    above the cushions.

    On another note the Steinway dealership has refused to look at the
    piano so far and it is still under the short warranty.  Their dealer
    tech broke a bunch of the drop screws trying to back them out further
    then they could so they were not unaware that a problem
    existed.  People in the UC system are encouraging the school to seek
    legal remedies as the camel's nose for UC to get their same Steinway
    problem addressed.  We may yet see a civil suit filed with the UC
    system offering amicus curiae briefs.  Wait till that story hits the
    front page of Music Trades!

    I obtained felt to bolster the whip cushions when the action starts
    capsizing but I've kept the springs strong and the key-pins
    polished.  The drop screws won't back out far enough to let the
    hammers rest anywhere close to the strings at drop so I don't have to
    worry about bubbling.  I hesitate to patch on more felt because this
    is a warranty issue Steinway should fix and I don't want to be in the
    middle "mucking it up."  When I called New York about it they sent
    action shims but no warranty service authorization.  I told the
    school they could pay me to do it or put the screws on
    Steinway.  They said Steinway WILL take the piano back and rebuild or
    replace it.


    And Andrew writes:


    I've had to do it on another piano with the red felt wrapped
    over.  Kind of ugly but that piano needs everything done to it and
    they asked me for the cheapest, quickest fix and they got it and
    like it fine.

    Sometimes reality just doesn't cut any slack for you,
    Andrew Anderson

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