Recrowning the soundboard,something different

[Farrell]

I guess you would want to make sure the panel-to-rim glue joint is in good shape! If your host would put about 20 cuts parallel with the grain in the panel and insert 20 shims at the same time, I 'recon that would indeed induce some crown. Or maybe what you need to do rather is put a whole bunch of transverse cuts across each rib and pull up on the board and goosh in a little epoxy in these along with the bridge job. No doubt all these methods would induce some crown. Maybe doing all three chop and squish procedures would do it?

Believe me, I only have room for criticism of these approaches, but I guess I have to wonder about the piano that is going to be restrung and definitely will not get a new board to replace the warped one. These pianos and piano owners do in fact exist. But maybe valve springs between the ribs and framing would work just as well. Certainly much easier. And certainly better than the cork wedges I have found on a number of pianos!

Just ramblin' thoughts.

Terry Farrell
  
----- Original Message ----- 
From: "Wayne Hohle" <wayne.hohle@sympatico.ca>
To: <pianotech@ptg.org>
Sent: Saturday, May 25, 2002 8:10 AM
Subject: Re: Recrowning the soundboard,something different


> hi list
> a recent chapter meeting our host explained that he improved sound board crown
> by cutting through the  treble-tenor bridge, perhaps in two or three places, to
> the soundboard. then he placed a heavy beam across the rim and with a
> turniquiot[spelling?} pulled the sound board up to open up the cuts in the
> bridge to a predetermind measurement. then he taped of the side of the bridge at
> the cuts and filled them with west epoxy to dry overnight. the next day he would
> remove all the stuff and go on to rebuild the piano.  he says the tone is nicely
> improved.
> any thoughts
> wayne
> 
> p.s. is there really  20 tons of pressure on the soundboard or is that on the
> frame and the pressure at downbearing at the bridge is something different
>