Uffe Bærentsen wrote:

Hi

Got a SB9" with flat belt drive.
The belt tends to slip when I use low speed so the belt drives itself of
the spindle pulley.
How do I prevent the belt from slipping?
The pulleys have been cleaned with degreasing fluid.
Hav tried to look at the line-up of the pulleys and they seems to be
perfectly in line.


The pulleys have to be aligned, but ALSO, the shafts have to
be parallel. On some machines, the shaft that drives the pulley
can be tilted slightly with the bolts that mount it. If you
get that right, the belt will walk up to the crown on the pulley
and then stay there. If you totally stall the spindle, then the
belt might walk off, but not when both shafts are turning.

Jon