Pianotech

  • 1.  M damper upstop rail

    Registered Piano Technician
    Posted 07-25-2022 10:20
    Greetings all,
    I came to a recently purchased (rebuilt, date unknown) 1978 M and found an odd problem: I could not get the damper upstop rail low enough. The other regulation parameters seemed reasonable: dampers to key lift and pedal were ok. In the photo you can see the rail is at the bottom of its travel. Anything I should look for?

    One thing that crossed my mind is that the back action is painted black. Perhaps it's not original? Do I need to simply redrilll the screw holes?

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    Scott Cole, RPT
    rvpianotuner.com
    Talent, OR
    (541-601-9033
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  • 2.  RE: M damper upstop rail

    Registered Piano Technician
    Posted 07-25-2022 10:21
      |   view attached
    Sorry, forgot to attach a photo:

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    Scott Cole, RPT
    rvpianotuner.com
    Talent, OR
    (541-601-9033
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  • 3.  RE: M damper upstop rail

    Posted 07-25-2022 10:33
    The ""rebuilder"" sprayed the backaction, a hack job. He didn't even clean the dust off of the tabs. Simply relocate the screws lower. You might have to plug the old holes. I use #8 square drive drawer front screws (built-in washer) from Mcfeeleys for this.  Plan on plenty else being not quite right.​

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    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
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  • 4.  RE: M damper upstop rail

    Registered Piano Technician
    Posted 07-26-2022 06:56
    Oh, look. Carbon-fiberized!

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    William Ballard RPT
    WBPS
    Saxtons River VT
    802-869-9107

    "Our lives contain a thousand springs
    and dies if one be gone
    Strange that a harp of a thousand strings
    should keep in tune so long."
    ...........Dr. Watts, "The Continental Harmony,1774
    +++++++++++++++++++++
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  • 5.  RE: M damper upstop rail

    Registered Piano Technician
    Posted 07-25-2022 14:50

    How does the upstop feel with the pedal and key depressed simultaneously? Oftentimes on these older Steinways, what feels like too much free play (when testing via lifting damper after depressing sharp) tightens up when the pedal and key are depressed simultaneously.

    If those check out, then it's relocating screw holes for the win. I've never seen the back action oversprayed like that. Very sloppy indeed.

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    Marc Abram RPT
    Highland MD
    (202) 468-8270
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  • 6.  RE: M damper upstop rail

    Posted 07-25-2022 15:06
    I forgot, 
    There will be a difference between key lift and pedal lift. Since the pivot for the tray is behind the underlever flange centers, the pedal lifts higher than the key lift.
    So check the free play in the damper with the pedal engaged. The upstop rail may be in the correct position.

    Pedal lift should lift to the point that the key lifts the damper. But when the key is held and the pedal engaged, the rear of the tray rises and so does the underlevers.

    If you adjust the upstop rail to the key lift, the pedal with jam the underlevers into the upstop rail and lower the front of the underlever restricting the upwards motion of the key and damper.

    If the tray pivot is in line with the flange centers, this does not happen.

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    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
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  • 7.  RE: M damper upstop rail

    Registered Piano Technician
    Posted 07-25-2022 16:21
    Greetings,
       There are a number of reasons the unstop rail cannot be lowered enough.  If the back rail cloth was changed to a thinner one, everything to do with the damper will need to be lowered.  If the key end felt was changed to a thinner felt, same thing.  If both of the above occurred, you will probably need to drill new  holes or make a new rail.  If this is the case, the increased downward angle of the under levers will perhaps have dug trenches in the key end felt. 
    Regards, 





  • 8.  RE: M damper upstop rail

    Registered Piano Technician
    Posted 07-26-2022 08:06
    Scott,

    Jon Page has hit the nail on the head (reply #6). The Steinway damper tray is a non-concentric animal: the pivot center of the underlevers and the pivot center of the tray are not the same. Thus when the underlever is raised by the keytail (and the sustain pedal is at rest) the underlever's azimuth is X;  when the underlever is raised by the damper tray (the susain pedal is actuated) its azimuth is Y. The upstop rail is asked to check (govern) underlever rise identically in both scenarios. It's a mechanical impossibility. It's an inexplicable design.
    Set your upstop rail the best you can to accommodate both modes of operation and call it a day.
    Until a damper tray in a Steinway piano is replaced with one of concentric design this dilemma can never be solved.



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    David Hughes RPT
    Vintage Case Parts
    Glyndon MD
    (443) 522-2201
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  • 9.  RE: M damper upstop rail

    Registered Piano Technician
    Posted 07-26-2022 10:46
    David, thanks. I've done many S&S upstop rails before and never had a problem. Generally, my starting point is (assuming the key lift and pedal are correct) is simply loosen the rail and prop up the pedal with a mute. On most pianos, that usually gives a tight fit--no slack at all. From there, I simply prop up the damper tray just a little with something, usually a block of wood with a a selected punching on top. That gives me the tiny bit of slack when hitting a sharp key at a MF blow. In this case, the rail simply is at the bottom of its travel and there's too much play in the damper.
    I'll be seeing the piano again soon. Maybe there's something else I haven't thought of. I'll recheck both lift from key and pedal.

    Anyone know what the diagonal slashes are in the photo above?
    By the way, the rebuilder also heavily spray-painted the bottom of the piano black as well, leaving overspray on the bottom of the soundboard.
    Not sure why they thought it necessary. It is stealthy though...

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    Scott Cole, RPT
    rvpianotuner.com
    Talent, OR
    (541-601-9033
    ------------------------------



  • 10.  RE: M damper upstop rail

    Registered Piano Technician
    Posted 07-26-2022 12:54
    Greetings,
       After the dampers and key dip are regulated, I set the pedal to lift the dampers exactly as high as the sharps.  then I can remove the action and set the stop rail just enough  to give me clearance above the sharps, usually about 1/16" higher than the pedal lift. .

       It helps to minimize the differences to make sure the dampers are regulated to the keys with the tray as close to final position as possible, but there is still going to be more clearance when the damper is lifted with the keystroke than when the pedal is also depressed.  Some of the Steinways are closer than others, but they all have this problem.  And, excessive free play IS a problem when someone is playing hard. 
    Regards,