Pianotech

  • 1.  Warped spring rail

    Registered Piano Technician
    Posted 10-22-2022 15:28
    Hello all,

    Occasionally on cheap consoles from the 1960s there are issues with the spring rail warping towards the dampers:



    There are no shims that I can remove. I can remove material from the rail where it is screwed to the action brackets, but I am concerned that the hammer shanks might hit the back of the rail since the bend is so extreme.

    The client lives more than an hour away, so ideally this could get fixed in their home. Maybe drilling a new screw hole in the bass farther in to try to pull it in?

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    Peter Stevenson RPT
    P.S. Piano Service
    Prince George BC
    (250) 562-5358
    ps@pspianos.com
    ------------------------------


  • 2.  RE: Warped spring rail

    Member
    Posted 10-22-2022 16:11
    Screw a metal rail, curved opposite if needed. Space the screws between the springs. Height is possibly limited to what will clear the damper screws/barrel. An angled metal (90 degrees) would be ideal if there's room.

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

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



  • 3.  RE: Warped spring rail

    Member
    Posted 10-22-2022 16:18
    Slicing kerfs and inserting a wider pieces of wood would straighten it out too but it's a lot more work. I wonder if screws would do the same thing but there's a risk of splitting the rail, the rail is weaker vertically more so than horizontally.

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

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



  • 4.  RE: Warped spring rail

    Registered Piano Technician
    Posted 10-24-2022 13:38
    Thanks, Jon. Do you mean something like this?
    https://www.rona.ca/en/product/reliable-solid-bar-90-angle-steel-black-4-ft-l-x-3-4-in-w-x-1-8-in-t-ap3448-13997775

    ------------------------------
    Peter Stevenson RPT
    P.S. Piano Service
    Prince George BC
    (250) 562-5358
    ps@pspianos.com
    ------------------------------



  • 5.  RE: Warped spring rail

    Member
    Posted 10-24-2022 23:23
    yes, but the ¾" portion would have to be cut to the width of the rail or a little longer. The 1'8" portion would be good for the vertical portion.

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

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



  • 6.  RE: Warped spring rail

    Registered Piano Technician
    Posted 11-07-2022 20:00
    So I ended up using a straight 3/4" steel bar. There were no clearance issues, and it straightened out the rail enough that the damper wires aren't blocking up against the felt. However, I was surprised at how much the metal ended up bending along with the rail. It's still bent, just not as bad.

    ------------------------------
    Peter Stevenson RPT
    P.S. Piano Service
    Prince George BC
    (250) 562-5358
    ps@pspianos.com
    ------------------------------



  • 7.  RE: Warped spring rail

    Member
    Posted 11-07-2022 20:50
    You could have slightly bend the steel in the opposite direction to end up more straight.

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

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



  • 8.  RE: Warped spring rail

    Registered Piano Technician
    Posted 30 days ago
    I don't know how much clearance you have under the spring rail, but rectangular tubing would have more rigidity than solid metal.
    Just a thought
    David D.





  • 9.  RE: Warped spring rail

    Registered Piano Technician
    Posted 30 days ago
    Do you mean under the spring rail or behind the spring rail? I put the metal on the player-side of the spring rail. The limiting factor there is making sure that the hammer shanks don't hit the metal. I'm not sure there is enough clearance for anything much thicker. Perhaps Jon's idea of bending the metal the opposite direction first might have helped.

    ------------------------------
    Peter Stevenson RPT
    P.S. Piano Service
    Prince George BC
    (250) 562-5358
    ps@pspianos.com
    ------------------------------



  • 10.  RE: Warped spring rail

    Registered Piano Technician
    Posted 29 days ago
    Hi Peter,
    Looks like you've resolved the issue, never the less I'll share my experience with what I believe to be the same problem some time back.
    I found the mounting areas for the rail on the back of the brackets to not be flat and true due to crude casting. I trued these up with a file and shimmed needed
    to get the rail to behave.

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    Fenton Murray, RPT

    Fenton
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