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Wedging a board in a bridge recap job

  • 1.  Wedging a board in a bridge recap job

    Member
    Posted 03-31-2020 20:48
    I usually do full board/bridge jobs where the finished pinned bridge is applied to the board...ie there is no pinning or hammering done insitu to the installed board. However, I'm doing more partial jobs now, and see this trend continuing as the economy becomes more difficult.  So...wedging a board, while driving bridge pins seems like a simple task. But, in the tenor and bass areas of the board,which have much more movement because of longer spans, I have not come up with a way to really wedge the board so it doesn't loosen up and start bouncing around, after just a few unisons.

    Any tricks out there on better ways to wedge the board...seems like a no brainer, but, I have not come up with a good way to do this yet. I wedge between beams and ribs under the bridge, and also put go bars, floor to rib in high excursion areas of the board. I find the go bars boingle out pretty often.


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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 2.  RE: Wedging a board in a bridge recap job

    Registered Piano Technician
    Posted 03-31-2020 21:14
    I've had reasonable success using machinist jacks on thick felt on a sturdy sawhorse with a 1 x 4 across two ribs. I have done it inside my soundboard press with a couple of go bars from above to provide stability and minimize movement.

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    Karl Roeder
    Pompano Beach FL
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  • 3.  RE: Wedging a board in a bridge recap job

    Posted 03-31-2020 23:24
    It may help to check your wedges too. If the angle is too steep then you have more problems. I've had success with making them as long as possible and keeping the angle as shallow as possible. Plus i make them wide, usually out of a 2 x 4.

    -chris

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    If it's pinging, it's not singing, it's just ringing,
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Knoxville, TN
    865-986-7720
    ------------------------------



  • 4.  RE: Wedging a board in a bridge recap job

    Posted 04-01-2020 11:20
    I believe when I was taught this, I found the pins drive in so much easier when the board doesn't bounce. Any carpenter can tell you that. Then there is the noise factor. It goes down when you wedge.
    The wedges they had in the shop had thick leather wrapped over the point and glued on. The taper was long. The more the merrier.
    They didn't fall out.
    Also you don't want to to damage the beautiful ribs with wood on wood.

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    Keith Roberts
    owner
    Hathaway Pines CA
    209-770-4312
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  • 5.  RE: Wedging a board in a bridge recap job

    Registered Piano Technician
    Posted 04-01-2020 14:14

    One should always wear ear protection when driving bridge pins whether the board is wedged or not. In terms of creating a less flexible platform there's no reason you can't wedge the board down rather than up. The non linear spring quality means that the assembly will stiffen as you wedge it down. 

    One place where I think it is important to insert wedges, whether you wedge the entire board or not (I don't), is between the bass cantilever (if there is one) and the panel. You don't want to drive these wedges too much as you will be possibly stressing the bridge/panel glue joint. That means you might have to tap them back into place periodically as driving pins in that section will tend to work the wedges out. 



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    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
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  • 6.  RE: Wedging a board in a bridge recap job

    Posted 04-01-2020 14:46
    In a shop where there are other people working and need to communicate, keeping the noise down is vital to safety. All by yourself,, you won't hear anybody yelling for help anyway,,, lol. Hopefully not

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    Keith Roberts
    owner
    Hathaway Pines CA
    209-770-4312
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  • 7.  RE: Wedging a board in a bridge recap job

    Posted 04-01-2020 15:17

    My experience with driving in tuning pins and bridge pins is the best way it to to support the pin block or the sound board directly to a concrete floor. I use an old back post of a deceased piano, and a piece of leather. You have to move the support a few times.
    Not only the sound board can flex, the whole body of the piano can flex, even the casters.
    You feel the difference in your hammer.



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    Michiel van Loon
    MEPPEL
    The Netherlands
    +31655150644
    mvanloon@xs4all.nl
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  • 8.  RE: Wedging a board in a bridge recap job

    Registered Piano Technician
    Posted 04-01-2020 15:59
    Definitely support the pin block when driving tuning pins.

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    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
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  • 9.  RE: Wedging a board in a bridge recap job

    Registered Piano Technician
    Posted 04-01-2020 01:58
    I've never found it necessary to wedge the board from underneath to pound in bridge pins.

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    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
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  • 10.  RE: Wedging a board in a bridge recap job

    Registered Piano Technician
    Posted 04-01-2020 08:21
    I've done many, many bridge repairs and done both wedged and un-wedged.  I'm more comfortable wedging.  Something about sending all that abnormal intense energy into the board really makes me wonder about the long term integrity of the board.  I've used all the methods mentioned in this thread.  What I've chosen in the end is a longer piece of thin delignit padded with felt that spans a couple of beams.  It is re-positioned periodically and secured with wedges between the beams and delignit strip.   The padding protects the soundboard ribs from damage.  Easy to install and move.  Always keep checking the wedges.

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    Tim Coates
    Sioux Falls SD
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  • 11.  RE: Wedging a board in a bridge recap job

    Member
    Posted 04-01-2020 08:36
    so does the padding help keep it from shaking out better?

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 12.  RE: Wedging a board in a bridge recap job

    Registered Piano Technician
    Posted 04-01-2020 09:26
    It's been my imagination that the felt pad keeps the jack from bouncing off of the horse. But then I'm applying pressure from both sides so who knows. The padding might just be there to keep the elephants away. Haven't seen any. Must be working.

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    Karl Roeder
    Pompano Beach FL
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  • 13.  RE: Wedging a board in a bridge recap job

    Registered Piano Technician
    Posted 04-01-2020 09:34
    The padding protects the under surface of the board and keeps the wedges from moving.

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    Tim Coates
    Sioux Falls SD
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