Hi.  I have a Philipps Pianella fitted with a roll changer.  Dale Rowe
suggests that the original Philipps examples were fitted under a shelf.
Mine is fitted above and fixed to a shelf.  There is no structure above
it apart from the separate xylophone which is some inches higher than
the top of the changer.

I can also confirm that the mechanism is constructed almost entirely
of steel, some with nickel plating and some un-plated.  Even the gear
wheels are steel.

The Philipps changer is very heavily constructed with the round
cross-struts being about 0.5" in diameter and the plates about 0.375"
thick.  It was not intended to flex!

Cheers,
Brian Cuff

 [ A catalog description of the Philipps Pianella roll changer is at
 [ http://www.mechanicalmusicpress.com/history/pianella/wpo_revs.htm 
 [ -- Robbie