-- non-subscriber, please reply to sender and MMD --

After measuring several sizes of tubing and thinking about where and
when players and other mechanical music devices were first constructed,
I am convinced that the tubing is/was actually metric.

Is this in fact the case?  Is 5/32" actually 4 mm, and 7/32" really
5.5 mm?  Just curious.

Ed Keough

 [ The smaller brass tubes in my old pianos have these measured
 [ outside diameter (O.D.) and inside diameter (I.D.):
 [                   /-----O.D.-----/  /-----I.D.-----/
 [   Cremona (1913)  0.197" (5.00 mm)  0.140" (3.56 mm)
 [   Ampico (1920s)  0.156" (3.97 mm)  0.128" (3.25 mm)
 [ The Neoprene hose grips the brass tubing securely.  I don't know the
 [ 'size' of the hoses, nor the manufacturing tolerance.  -- Robbie