Topic Thread

  • 1.  Rocker actions

    Registered Piano Technician
    Posted 05-24-2022 10:39
    Hey Folks,

    I enjoy reading your muses here, thank you!

    Is there any info out there on servicing rocker actions? I get by on the rare occasion I see one, but wondered , as I often do, what I don’t know!

    Tried a journal search with no results.

    Andy


    Andrew J. Lyford, RPT
    3355 Mount Olivet Rd
    Martinsville, VA 24112

    pianotechandy@gmail.com

    1-276-732-6290

    “A painter paints their pictures on canvas. Musicians paint their pictures on silence”. Leopold Stokowski


  • 2.  RE: Rocker actions

    Registered Piano Technician
    Posted 05-24-2022 12:53
    I'm no expert, but the way I have regulated them in the past is to visualize them kind of like a see saw. When one end goes up, the other end goes down. 

    What makes it a little more complicated is what do you do when you want the back of the rocker to go up to eliminate lost motion, for instance, but it can't because the screw that's holding the back end is too far down, which makes it kind of like a really fat person sitting on the other end of the see saw, and you're only 75 lbs? So, you have to loosen the back screw first. Or, what do you do when the front of the rocker is already down on the key? In that case you have to do a double release. Loosen the front and back a few turns, and then see where you're at.  

    It's not very complicated and you'll get the hang of it after doing a few keys. 

    Wim





  • 3.  RE: Rocker actions

    Registered Piano Technician
    Posted 05-24-2022 13:27
    Thank you guys, I do have the tool and have had good luck adjusting the rockers in the past, but your comments are helpful and appreciated. I was wondering about taking the action apart for service, that sort of thing. I will have to do some key work. Looks like I can get by without detaching all the keys.
    This is from a partially restored 9 ft Knabe, and the work seems pretty nice. Original parts, new Renner hammers. I will have to reduce the size of upper treble hammers, and some good basic service. Its not the disaster I dreaded when I got the call!
    Andy




    Andrew J. Lyford, RPT
    3355 Mount Olivet Rd
    Martinsville, VA 24112

    pianotechandy@gmail.com

    1-276-732-6290

    “A painter paints their pictures on canvas. Musicians paint their pictures on silence”. Leopold Stokowski




  • 4.  RE: Rocker actions

    Registered Piano Technician
    Posted 05-24-2022 13:11
    1) Get a "Bechstein screwdriver" from Pianoforte Supply.
    2) The technique:
         a) The front screw moves the capstan up, the back screw moves it down.
         b) Depending on which way you want to move the capstan, call one screw the "mover" and the other the "retainer."
         c) Loosen the "retainer" a little.
         d) Turn the "mover" just enough to get the capstan where you want it, and just a tiny bit more.
         e) Tighten the "retainer", watching to just bring everything into perfect alignment, i.e. taking back the "tiny bit more" and firming the position of the rocker.
    It's a very pleasing job with the right tool and technique.


    ------------------------------
    Ed Sutton
    ed440@me.com
    (980) 254-7413
    ------------------------------



  • 5.  RE: Rocker actions

    Member
    Posted 05-24-2022 22:04
    If the front of the rocker arm is touching or very close to the key and you need to get more height, place a spacer under the rocker arm to gain the height you need (do the set). BTW every adjustment on these is very tediously time consuming, again and again.

    ------------------------------
    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
    ------------------------------



  • 6.  RE: Rocker actions

    Posted 06-01-2022 13:52
      |   view attached
    Sure, rocker capstans take more time to adjust that regular capstans. Tedious? Maybe, although I might argue that is a question of one's attitude.
    Of course, the right tool is essential to retain one's sanity . see photo.

    Here is e instruction sheet that I have put together for use of the offset screwdriver I have supplied:
    Use:
    To adjust rocker capstans, you have to go back and forth between the back and the front screws, adjusting both of them as required. To raise the hammer line, the back of the rocker capstan has to be raised and the front needs to be lowered, and vice versa.
    
To lower the front of the rocker capstan in order to raise the hammer:
    - loosen the back screw.
    - tighten the front screw an appropriate amount
    - tighten the back screw (with sensitivity)
    - check hammer height, adjust as needed

    To lower the hammer:
    - loosen the front screw.
    - tighten the back screw an appropriate amount
    - tighten the front screw (with sensitivity)
    - check hammer height, adjust as needed

    Notes:
    The slender handle allows the user to roll the tool between their fingers to select the appropriately angled blade for the specific orientation of the screw slot. Roll the tool to the left when re-setting the tool in tightening, and to the right when loosening the screws, and the blade will line up with the screw slot. Never use the tool in a combination handle or similar – it will slow you down too much.

    Because of the handle length, there is a lot of leverage (torque) that can be applied to the screw and the rocker capstan. Avoid tightening the rocker capstans down too much. Use this tool with sensitivity in your fingertips and some common sense and caution. The rocker capstans are well over 100 years old, many are brittle, and they can easily break in two.

    When finished adjusting, the hammer should be in its correct position and the rocker capstan should be held tightly enough that it will not move, even if the wood dries out more. But it should not be clamped down so tight as to risk breakage.

    ------------------------------
    Jurgen Goering
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  • 7.  RE: Rocker actions

    Registered Piano Technician
    Posted 06-01-2022 16:23
    Dear Juergen,

    Thank you for the info. I do have the tool and once I got going it was no big deal. This tool is essential, no question!!!!
    They really aren’t too bad to work on, I had to solve some issues with jacks having pressure and breaking, like any action would, but it came out quite nice. The partial restoration work before me was quite well done for the most part , that helped a lot.
    Andy

    Andrew J. Lyford, RPT
    Lyford Piano Works