If real slow speeds are wanted, then a 1100 rpm motor can
be used.

Probably an 1100 rpm motor would be hard to come by in an AC machine.
That'd be a 6 pole machine, synchronously speaking. Pricey?

Bob Swinney
"jim rozen" wrote in message
...
In article , says...

If you can find a pulley with the same set of steps as the ones
on the motor and the spindle (assuming that you don't already have three
pulleys), turn the motor pulley upside down, and put the third pulley on
a swinging arm, so moving the motor to tighten the belt tightens both by
moving the intermediate pulley. My Taiwanese drill press (16 speeds)
came with a hole in the belt guard and the headstock casting which
serves as the pivot point for the idler pulley arm. (The idler pulley
has an extra step on it and the motor pulley is shifted a bit to
maximize the number of speeds available, with more options to reduce the
motor speed than to increase it.

Another cute way to do this is to replace the existing motor
with a 3 phase unit, and power from a VFD. For those who
can throw money at a problem like this, it's really the
way to go.


==================================================
please reply to:
JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com
==================================================