Hi everybody:  Now I'm trying to put in working condition a Carlton
Wurlitzer player piano, so I'm asking if somebody can explain to me
how works the mechanism of the top action which allows that the roll
doesn't move to the left and the right, so the perforations can go
exactly to the hole of the tracker bar.

At the right of the tracker bar there is a thin thread which wraps
(spins) onto a metal axle, which is connected to a metal wheel with
two little brakes.  One more time thanks!

Horacio Asborno,
Viedma, Rio Negro,
Patagonia Argentina