Warped grand piano lid

[Ron Nossaman]

>Hi list, One of my next contract jobs is a grand where the lid has warped
>considerably, might be described as an S shaped crown as Ron might put it,
>but this is a lid, not a soundboard. Warp is such that at the right hand
>corner (by hinge) is about half an inch up when lid "closed". This happened
>some time ago when I believe owner had it in storage somewhere. It is
>figured walnut and weighting cost of feasable repair against replacement. I
>had thoughts of pvc go bars as recently described except workshop has very
>high ceiling and not sure how much pressure for how long if this is an
>option.
>
>Thoughts, suggestions, comments welcome.
>
>
>
>NB. rest of piano due in for restring/action work
>
>Brian Lawson




Well, you need to make up some flat "ribs"...

Just kidding, what this sounds like to me is the old
"propthelidupandleaveitthereforfortyyears" gravity warp. I've heard claims
to the effect that shimming under the lid at the tail curve (2 o:clock if
the keybed is 6:00), and weighting the high corner for a few weeks can
straighten it back out somewhat. That's not an endorsement, because I
haven't tried it, but that's all I've got by way of help.

Luck,
  
 Ron N