I looked into a VFD for my mill but decided against it. Part of the reason
was expense (the spindle motor is 10hp so a VFD is lotsa $$) but the main
reason was that all the information I could gather said that the VFDs didn't
like to ramp up one motor and then ramp up another. My table drive motor is
3hp, so after the spindle is going I'd need to turn on/off the table drive,
plus there's a light and a coolant pump. I still need to build a rotary
phase converter for this machine..... this winter for sure.

al.



"Carbonite" wrote in message
oups.com...
Another question would be should I use a VFD unit instead of the rotory
phase converter? From what I can tell ,I can ramp up the spindle speed
of the mill and would not get that surge.