Restoring crown in old soundboards

[Farrell]

There are old PTG Journal articles on this process. I did this on my first restringing job - little Estey microgrand. I dried the heck out of the board - cracks opened up all over the place. I wedged in blocks between ribs and framing until I heard c-r-a-c-k-i-n-g (and in some cases, until I heard C-R-A-C-K-I-N-G!). I did the Spurlock shim method. Installed at least 20 shims - maybe more. Man, that thing bellied up like nothing you've ever seen before. Give that rascal a sharp fist in the middle and you got this massive (relatively speaking) B-O-O-M out of the piece of trash soundboard. Strung that puppy up (with carefully measured downbearing), measured crown - and found that the board was at best F-L-A-T.

Hey, but it sure looked good! Funny thing is, the piano went into a new home in a room all its own (maybe 15' by 15') with tall ceiling, oak floors, no rugs and no curtains - echoes all over the place. Piano really doesn't sound half bad in there. The owner loves it! I think a good powerful Steinway would be a disaster in that setting!

Terry Farrell
  
----- Original Message ----- 
From: "Alan Forsyth" <alanforsyth@fortune4.fsnet.co.uk>
To: "Pianotech" <pianotech@ptg.org>
Sent: Tuesday, April 15, 2003 7:50 PM
Subject: Restoring crown in old soundboards


While the list is discussing soundboard crown at the moment, I thought I
might mention that a piano dealer sent a 100 year old Steinway grand with a
badly cracked soundboard back to the factory in Hamburg for restoration.
Well, £8000 ($12k) and 3 months later it came back sounding perfect. To my
surprise, I was told that, the factory did not install a new soundboard but
instead repaired the original by shimming, i.e. filing in the cracks with
those V shaped wedge fillets.
 When I was at piano college we were told that this is a method used to
restore crown "in situ" as it were. The theory, I suppose, is that if you
wedge more material into the panels, it will force the panels to bow or bend
back into shape. I have not yet had the opportunity to put this to the test,
but have any of you tried this method or think it feasible.

Regards
Alan Forsyth
Edinburgh
   "Madam, all pianos sound horrible, but if you play music on them they
sound very nice!"  (from my forthcoming book, "A Day In The Life Of a Piano
Tuner" by yours truly)

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