I've been told by a machinist I trusted that
the vari-speed heads are more trouble than
they are worth. I'm sure we'll hear from
everyone that has had a vari-speed for 30 years
and no problems, but I'd stick with a stepped
pulley and VFD.




One of my mills has a vari-speed head on it. And I hate it. It needed a
rebuild with less than 2000 hours on it. Though it is rated at over
7000 RPM, anything over 3000 sounds pretty bad.


I'd stick with a stepped
pulley and VFD.