Pianotech

  • 1.  S&S dmapers hanging up after service

    Registered Piano Technician
    Posted 05-06-2021 05:54

    My son, who works with me, serviced a S&S B yesterday.  He said it was in good condition.  He tuned it, did a light hammer filing, and some voicing.  When finished, he put the fallboard, cheek blocks, and keyslip back in and as he started playing, some dampers were hanging up. Mostly in the bass and low tenor.  If he removed the cheek blocks and pulled the action out just a 1/16 of an inch, the dampers would drop down.  But every time he put the cheek blocks back in and screwed them down the problem returned. 

    We did some trouble shooting over the phone but could not solve the problem.   He said there did not seem to be interference from the sostenuto rod or sostenuto tabs.  He  did not leave any tools inside the action cavity.  The metal brackets mortised into the cheek blocks are screwed in tight.  The guides on the ends of the key frame are secure and not bent. 

    The piano played fine before he did any work. I am going out there later today.   I can't think of any way the position of the action could change or what could be causing the interference.

    Thanks,

    David Weiss



  • 2.  RE: S&S dmapers hanging up after service

    Posted 05-06-2021 07:28
    It's the sostenuto hanging up. I've had this happen. I'd go with the metal brackets in the cheek blocks, or the cheek blocks themselves.  If cheek block dowels are worn, or the brackets slightly worn, the action will not go back in exactly where you want it. I'd increase the clearance between sostenuto and tab pickups on the damper top flange, by adjusting the silly S&S sostenuto mechanism.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 3.  RE: S&S dmapers hanging up after service

    Registered Piano Technician
    Posted 05-06-2021 10:37
    If it's not what Jim said, I would look into the possibility that the sostenuto rod bracket screws in the bass and possibly at the bass / tenor break are loose, allowing the bar to have migrated towards the sostenuto tabs in that part of the scale when the hammers were filed.

    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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  • 4.  RE: S&S dmapers hanging up after service

    Posted 05-06-2021 07:32
    Most likely it is sostenuto. Try pulling action slightly out - of Demper problem disappear it is definitely sostenuto. Solution - reposition the action if hammer line permits or reposition the sostenuto. Keybed humidity related movement sometimes is enough to mess the sostenuto.

    Alexander Brusilovsky




  • 5.  RE: S&S dmapers hanging up after service

    Member
    Posted 05-06-2021 11:28
    Another idea is to loosen up the screws that secure the cheek blocks or tighten them if they are loose. Its seems like a positioning problem. I would also check the action bracket screws for tightness as well as the monkey. The positioning adjustment on the right block may need an adjustment to make sure it is holding the action frame. Perhaps a shim of veneer is also needed on the back of the key frame to keep it from being positioned too far in.

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    James Kelly
    Owner- Fur Elise Piano Service
    Pawleys Island SC
    843-325-4357
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  • 6.  RE: S&S dmapers hanging up after service

    Registered Piano Technician
    Posted 05-06-2021 16:07
    Thanks for all the replies.  It turned out to be quite easy.  The sostenuto rod bracket screws were loose, allowing the rod to move.  That explains why it was fine when my son got there, but not so fine when he tried to close the piano up.  Really appreciate the help from this list.

    David

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    David Weiss
    Charlottesville VA
    434-823-9733
    davidweisspiano@gmail.com
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