Dave Krall said in 010316 MMDigest:

> I'm converting an old Simplex spool box for a roll inspector.
> Can anyone suggest a small 12-15 volt D.C. variable speed motor
> that would be suitable to power it?

The late Harry Medcraft of Harrow (NE London) who cut new and reissue
Duo-Art rolls in the 1970s completely re-engineered his electric-only
Duo-Art grand, such that when you lifted the covers it looked like a
small spaceship disguised as a piano.  His roll drive employed a
Volkswagen Beetle windscreen (windshield) motor which he said was the
most reliable 12V motor you could get.  However, he obtained variable
speed from it by swinging it on gimbals around the centre point of a
metal sphere on its shaft, in contact with which a small rubber-tyred
wheel took off the roll drive.  The roll speed thus depended on the
angle at which the motor plus its frame were positioned.

You would expect the rubber drive to slip but his piano would play the
big Frank Adams jumbo rolls perfectly satisfactorily.  It's still in
the keeping of his widow Sylvia.

Dan Wilson, London