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It wasn't like this before

  • 1.  It wasn't like this before

    Posted 13 days ago
    While working on a grand piano, I removed the action cradle and performed work on some sticking jacks. when I put the action back onto the keybed, i noticed it was like this.....(see image), the treble hammers seemed to be sitting very high above the hammer rest and that the hammers would no longer fit under the pin block without a lot of manipulation.  I can't understand what changed. 


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    Gary Howell
    Buckeye Piano Tuning
    Massillon OH
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  • 2.  RE: It wasn't like this before

    Registered Piano Technician
    Posted 13 days ago

    You may have tightened the upstop rail down to far in the treble area. Should be able to lift sharps about 2 mm
    Gary Bruce
    Registered Piano Technician





  • 3.  RE: It wasn't like this before

    Registered Piano Technician
    Posted 13 days ago
    Hi Gary:
    You removed the "action cradle". You mean the "stack"? The action brackets and everything connected to it? What exactly did you do on the jacks? Were they all under the knuckles before you started? Did you do any adjustment to the capstans in the process? If the action brackets were removed and the bracket feet are lower than before when you replaced the stack on the keyframe, the symptoms would be as you describe. We need a bit more information.
    Paul McCloud
    San Diego




  • 4.  RE: It wasn't like this before

    Posted 13 days ago
    Hi Paul,

    I lubricated the center pins on the jacks to alleviate some sluggishness. I removed them from the stack and replaced them in the same order.

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    Gary Howell
    Buckeye Piano Tuning
    Massillon OH
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  • 5.  RE: It wasn't like this before

    Registered Piano Technician
    Posted 13 days ago
    Ok. So, reading some other posts, maybe you tightened the upstop/shipping rail so the keys are held down? If you remove it, do the keys and hammers return to normal?
    Paul




  • 6.  RE: It wasn't like this before

    Registered Piano Technician
    Posted 13 days ago
    Hi Gary, take the stack screws back out  ....  all the way out.  Lay them aside.  Remove the stack and then place it back in position.  Make sure all the brackets are in their place .... all the way down resting on the key frame.  If the screws in the in front of the stack are slanted they go in last.  Screw in the end screws first, the back ones.  Now screw in the two front ones on the end brackets.  All four of these screws should screw in directly up and down, perpendicular to the action frame.  Now screw in the rest of the back ones, then the fronts ones last.  Or in other words, screw in the slanted ones last if there are any.

    It sure sounds like you may have gotten the stack out of whack with relationship to the frame.

    Granted the upstop rail when installed improperly will cause the hammers to lift but usually only where the support posts are, not on the ends.

    Let us know what you find.

    Lar


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    Larry Fisher
    Owner, Chief Grunt, Head Hosehead
    Vancouver WA
    503-310-6965
    Working the gravy zone for the rest of my days.
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  • 7.  RE: It wasn't like this before

    Registered Piano Technician
    Posted 13 days ago
    Another possibility is that the action bracket at the treble end was not screwed in all the way, and someone turned capstans in that area to "correct" the hammer line. Then, when you took it apart and put it back together, you actually screwed those same action bracket screws all the way in (like the good Lord intended). That scenario could yield what you are looking at.

    Alan

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    Alan Eder, RPT
    Herb Alpert School of Music
    California Institute of the Arts
    Valencia, CA
    661.904.6483
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  • 8.  RE: It wasn't like this before

    Member
    Posted 13 days ago
    Lots of good scenarios. Another one, which is probably not the culprit, is if the action spread increased in the treble (loose repetition rail).  My money is on Alan's scenario.

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    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
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  • 9.  RE: It wasn't like this before

    Registered Piano Technician
    Posted 13 days ago
    One thing to check to confirm Alan's scenario is to take a look at the capstans. Under most circumstances the capstans will all be turned up about the same height above the keys. If you can see 2 or 3 more threads on the capstans under the treble than the rest of the notes, this would validate Alan's theory, or something along those lines.

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    Steven Rosenthal
    Honolulu HI
    808-521-7129
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  • 10.  RE: It wasn't like this before

    Posted 12 days ago
    Alan has it right. I regulated in a rebuild shop and checking the stack screws before setting blow distance is essential. Just tightening the screws a half a turn can raise the hammers 1/2 inch.

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    Keith Roberts
    owner
    Hathaway Pines CA
    209-770-4312
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  • 11.  RE: It wasn't like this before

    Registered Piano Technician
    Posted 11 days ago
    Gary,
    Here is something else you might check, especially if only a cat's length of hammers is affected. This is a common occurrence in our shop and easily remedied!
    But seriously, my guess is that the action stack is not positioned correctly. Larry Fisher's procedure for replacing the stack frame screws is spot on. During that procedure you can also put medium pressure on the hammer rail to check that the hammers are not going to misbehave. Alan Eder and all the other contributors mention excellent overall hints. When the stack is off, it is a good idea to make sure there are not "false start" holes in those wood supports which would position the stack incorrectly to begin with.
    Joel & Pris
    Source of Excess Hammer Height


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    Joel Rappaport
    Rappaport's Piano Workshop
    Round Rock TX
    512-255-0440
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