We have a 48-key Piano Melodico (Racca?), and I read with some interest
the last several posts about it.  I  was surprised to see that it was
supposed to hold its tune.  Ours is not operating yet, and so I haven't
paid much attention to the tuning of it.  I restrung it and set it
aside for now.

I noticed that the back of the soundboard, at the rear of the piano,
does not have any rim that the back of the soundboard is glued to.  It
is glued on three sides, but not in that portion.  There's nothing
there to glue it to.  On a normal piano, the soundboard is glued down
all the way around the circumference of the board.

My question is: How does the piano stay in tune?  Wouldn't the down-
bearing of the strings pressing on the bridges cause the board to
compress downward, and, without being supported back there, wouldn't it
continue to collapse, making the tuning unstable?

Tony Marsico, Curator
Bayernhof Museum, Pittsburgh