Variable speed of fixed speed help

[Deema]

I have recently bought a Bridgeport clone that I’m slowly setting up. It came with a VFD to run the turret motor which besides converting it to single phase provided variable speed. Im re-wiring it, as it was......shall we say......unusually wired! Anyway, I have 3ph, so don’t need the inverter to run it on single phase. However, not having done much milling, is there a rgood reason to have variable speed or are the selectable speeds more than adequate?

 

[benmychree]

Selective speeds have served mankind very well for many years before frequency drives became all the vogue --- in my opinion at least.

 

[machPete99]

Its a lot easier to turn a knob than move belts around on step pullies, and optimize your cutting rates on the fly.
It also helps on mills without back gears to go into slower speeds.