I have a small Mortier orchestrion which was beautifully restored some
time back except for the rubber transport rollers, which had become
hard and misshapen after years of compression in a closed keyframe.
In spite of their condition, the organ still played beautifully if
I helped the book move by hand-turning the drive pulley.

I have recently had new rollers made in the Netherlands and have
reinstalled them in the keyframe.  I have tried adjusting the height
of the lower transport roller with shims all the way from below the
brass keycomb to so far above that the wooden bearings were close to
interfering with the bridge when closed.

At no setting have I been able to get the organ to play while the
book is moving; when I adjust the grooved roller by the time the organ
starts to play I have adjusted to the point that it clamps the book and
stopped the movement.

I have consulted Eric Cockayne's "Fairground Organ" book and though it
addresses the position of the grooved roller it does not offer any info
on transport roller position.  I have also looked in the MMD Archives
under Repairing, Repairs, Rubber, Rollers, etc., and I find no
references to proper adjustment.

I am therefore asking if anyone might have some advice on the correct
adjustment of the rubber transport rollers?  The brass keycomb has a
very slight angle upward towards the bottom roller.  I reasoned that the
top of the roller should be in line with the trajectory of that angle,
without success.

Thanking in advance anyone with suggestions.

Cecil Dover
Los Angeles, Calif.