Key level puzzle

[John Freeman]

Gary and Jean Isaac wrote:
> 
> One of the pianos I service at a Teachers College is a Dietmann upright
> bought new in 1990.  When I  serviced it six months ago it was in good
> contion, but now it has a problem that perplexes me.
> 
> Starting from F3 up to the top the front of the key level progressively
> rises until it measures a 1/2" gap above the front board.  The keys  are
> so far off the front rail that the top key will even play when I put my
> key level block under it.   Everything else sees to be in adjustment.
> Capstan heights are regular throughout.  Balance rail punchings are the
> same throughout.  The back rail  cloth is okay.  Action brackets on both
> ends are the same height. The keys are so high off the front rail that
> they can even move out of the slots when playing.  When the fall board is
> replaced the high treble keys are blocked so that they only way to render
> them playable is to shim up the fall board on the treble side.  Adding
> height to the back rail cloth brings the level down of course,  but then
> the capstans would have to be radically altered.
> 
> The music instructor in charge of the pianos says that he suspects the
> piano may have been dropped when being moved upstairs.  However, I cannot
> see any signs of damage.
> 
> Gary Isaac
> South Africa


I would suspect that wood support at the treble end which is glued and
screwed
to the back panels has been knocked loose.

John Freeman