In article , David Malicky
says...

Any other ideas?

What you propose can work, and others have done it here.

You will spend a lot of time doing it and it will be
fairly cumbersome when you are done - though it will
accomplish the goal of getting the spindle speed down
below 100 rpm.

There is another way that will cost a bit more but
give you a much nicer result, and make the drill
a great deal more versatile.

Replace the existing motor with a small three phase unit,
and run it off a VFD that is powered from 120 volt
single phase.

This is what I did at at work for my older SB drill
press that *should* have a jackshaft, but does not.

I mostly keep the belt on the lowest speed, occasionally
on the next speed up. But that setup will make the
spindle tick over at about 60 rpm with full torque.
Put an extra muffin fan on the motor to keep it from
overheating at the slower speeds.

Jim

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