Pianotech

  • 1.  soundboard repair

    Registered Piano Technician
    Posted 04-13-2021 22:40
    Hello All;
    I have a situation with the Steinert grand that I'm rebuilding. I had shipped it out for refinishing and the refinisher told me that he was going to repair the cracks in the soundboard
    and that he had experience. The repairs with the shims were excellent except for one detail--it looks like he used mahogany or ebony and there are dark streaks where the cracks used to be. I tried bleaching them but to no avail. The best result I've had so far is notching on top of each shim with a tiny dremel bit and then filling in with wood filler. It looks much better but not like a good like-colored splice. Does anyone have any suggestions for repairs other than reshimming?
    Also; it's been a while since I refinished a soundboard. Are they still using shellac? I picked up a can of "Stringed Instrument Lacquer" at Woodcraft.
    Any opinions on that? Thanks!

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    James Sasso
    Wrentham MA
    508-954-3624
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  • 2.  RE: soundboard repair

    Posted 04-13-2021 23:28
    You can route out the shims with the Spurlock bit and a Dremel Tool mounted on a track. I have the spruce shims (aged, so they should match).  I think I have the bit but not the track and mounting bracket.

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    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
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  • 3.  RE: soundboard repair

    Posted 04-14-2021 08:47
    You can add color to the epoxy if you use West system 5:1 or Jamestown's Total boat 5:1 epoxy.  Use the 410 microballoons filler with either the West or Jamestown, and tint with transtint dyes. The colors you most likely will use to create a match are: Honey amber, Brown Mahogany, and maybe Red(or orange). Honey amber is an amber (yellowish) tone. Brown mahogany is mostly brown, with a little red in it. The little bit of red can move the honey amber a little to the orange side of things, to match old shellac. 

    I'm getting better at it. One has to experiment, and also one has to allow for the difference finish will have on the final color...is all a bit of guesswork. We just diaphragmed the bass/tenor end of a Chinese makeover we are working on with a die grinder, while leaving the existing finish  on the rest of the board. The ground part of the board was crazy white compared to the yellowed board. Tiny tiny amount of transtint Red mahogany in water, dyed the patch to an totally acceptable match. Then satin finish General Finishes High performance, sprayed over the whole board evened the whole thing out.

    One thing you will find, is that when you spray the finish (keep it satin, not gloss) over the whole board, color inconsistencies recede, because the whole board  takes on a uniformity...the topcoat covers the whole board uniformly. You can still see the patches, but they just are no longer in your face. The match will not be perfect no matter what you do. The non-match just recedes under the topcoat's uniformity. I would have left his dark shims as they were, and made them a feature...remember, it is an old board. Trying to pretend otherwise, will tend to drive one nuts.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 4.  RE: soundboard repair

    Posted 04-14-2021 10:48
    ON seconf thought, it's not a Dremel Tool to use but an air grinder.

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    Regards,

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