Pianotech

  • 1.  Sluggish sustain pedal

    Posted 06-01-2022 19:59

    I did a service call on a 1993 Baldwin R with a QRS system installed (unplugged).  It will depress but VERY slow to come back up. I explored the trap work and felt it was in the lyre, so removed it and opened the pedal box. Removed the sustain pedal, applied some MPL-1 to the pivots, replaced and I worked it approx 50 cycles. Got a note today stating it won't return. Planning a trip on Friday morning to dig deeper. 

    I did remove action to check the back action. Cycled it by hand and it was very free moving.  I looked for a spring of sorts and didn't really see one.  Is there a spring within the QRS system that I'm not seeing?   Humidity 46%, temp 70



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    Les Koltvedt
    Marietta GA
    (734) 657-7034
    lkpianos@gmail.com
    https://www.lkpianos.com
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  • 2.  RE: Sluggish sustain pedal

    Posted 06-01-2022 23:00
    With each QRS install being a custom fit job, it's difficult to say.  In my experience, an older system can suffer from dirt in the pivot points of the sustain actuator levers that take the motion of the pedal solenoid and transfer it to the sustain lift rod.  Here is a link (below) of a quick video that illustrates the concept.  I ended up taking out both of the pivot bolts, cleaning and lubricating with Prolube.

    QRS Sustain Lever Service

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    Kendall Marquardt
    Edgerton WI
    (608) 963-6210
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    Original Message


  • 3.  RE: Sluggish sustain pedal

    Member
    Posted 06-02-2022 07:35
    Hi Kevin,  

    I don't believe there is a spring in the initial Pianomation kit.  A very recent journal article gave some great info on installing a flat spring in a grand piano.  The spring is attached to the left action stop block and extends over to the  left end of the damper lift tray.  The tension on the spring must be adjusted by bending the spring because you don't want to stress the solenoid and you don't want to make it too hard
    for the pianist to depress the pedal.

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    [Wesley] [Gill[Designation]
    Apollo PA
    (412) 480-6125
    WesleyGillWesley
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    Original Message


  • 4.  RE: Sluggish sustain pedal

    Member
    Posted 06-02-2022 10:50
    I am a little confused by the wording of your post since it says the player is unplugged. Is the problem that the sustain/damper pedal is slow coming up after it is depressed by the pianist or it stops moving freely ? There could be a problem with the bushing in the lyre pedal rod as well as the connection to the damper lift tray connection rod from the solenoid bracket . The rod replaces the typical pitman dowel . The solenoid bracket could be seizing up in the hinges/brackets it is mounted in . In the video that was posted there is a spring mounted at the back of the trapwork that could be binding or not in the slot or mortise. Finally the solenoid may be impeding the operation and needing replacement/testing/repair. If that is the case you may want to talk to QRS

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    James Kelly
    Owner- Fur Elise Piano Service
    Pawleys Island SC
    (843) 325-4357
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    Original Message