Z axis drive

Im doing a conversion on a large, square column, mill, like a RF-45, but
from Wholesale Tool

The Quill drive has a rewind spring to keep the quill up, and is driven
down by either a drill press style wheel or a worm gear and small handwheel.

I am considering driving the handwheel with a belt and stepper, and
hoping the rewind spring can be set strong enough to keep backlash down
to a workable level.

Has anyone tried this? It seems to me the forces are always cutting down
on Z, never when retracting, so the spring ought to do it.

ron ginger