Soundboard repair question

[Annie Grieshop]

That's exactly what I thought about the CA:  that it wouldn't so what needs
to be done.  But I also thought it was an interesting idea and didn't recall
ever hearing it discussed, so I figured I'd ask.  Other customers have asked
me similar questions, as well.

(Yes, I know the strings have to be removed before repairing with epoxy.....
<g>)

The pianos sound good -- great tone, no rattles -- so I'm mostly concerned
with getting them to pay attention to them.  The bigger cracks in the L are
along old repair lines, but none of them is particularly bad.

You don't fill cracks?  So, it's either replace the board or leave it alone?
(That seems really sensible.)  Under what conditions do you decide to
replace it, then?

Annie G.

> -----Original Message-----
> From: Richard Brekne [mailto:ricb at pianostemmer.no]
> Sent: Sunday, February 10, 2008 4:19 AM
> To: pianotech at ptg.org
> Subject: Soundboard repair question
>
>
> I dont think CA would do well for soundboard cracks.  Maybe if they were
> really thin hairlines... but I doubt it.  You can use an epoxy.  I have
> used West System epoxy in the past with great success for years and
> never had a sign of a soundboard re-cracking along the old crack lines.
> You tape the underside of the cracks so the epoxy doesnt just leak
> through. Use some good strong adhesive tape.  The epoxy does not need to
> behave like wood in the face of humidity changes. It just needs to hold
> on to the edges during tension periods and stand up under the pressure
> during compression periods.  The rest of the wood (probably 99.% percent
> of the total resultant panel) will take care of dealing with humidity
> changes.
>
> By the sound of your question I'd like to add that this kind of job is
> done with the strings removed.... just in case there was any question.
>
> If the pianos sound good, and the cracks are only thin more or less
> hairline in character... I wouldnt bother.  In fact I dont bother with
> filling cracks in soundboards anymore as a general rule.
>
> Cheers
> RicB
>
>
>     This question was posed to me yesterday by the facility manager of a
>     local
>     community center:  could a cracked soundboard be repaired by
> dripping CA
>     into the crack (as is done with bridges)?
>
>     My questions were:  would CA hold up and would it help?
>
>     I didn't know the answers to any of those, although I could
> hypothesize
>     some.  BTW, I told him NOT to try it, since both the pianos
> with cracked
>     soundboards are Steinways:  a 1950s B and a 1931 L that's been
>     rebuilt and
>     refinished.  And nobody ever mentioned (or remembered) to think about
>     humidity control.  Harrumph!  The cracks aren't horrid, but they are
>     there.
>
>     Thanks for any comments.
>
>     Annie G.
>
>
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