Quote Originally Posted by WilliamT4450 View Post
mactec- did you servo the spindle motor, or leave it an induction, single phase, three phase. and did you move from the R8 spindle?
reason is, i am moving from the 1hp-3phase to possibly a servo, still looking at the posibilities
The motor is a 3 hp 3 ph Bridgeport motor 3450 RPM some had these motors as standard, it is driven by a Yaskawa VFD Drive at 120 Hz giving it double the rated RPM, the spindle has a Erickson 30 Taper, which was also a standard on some machines, this spindle can run to 12,000 RPM as I have modified most of it, nothing in the Head is standard Bridgeport, the Head in the photo, is 5" shorter than the standard Head

A Servo can work quite well for a spindle drive, and you have the benefit of being able to set it up just like an axes and have very tight positioning control, you would need different type of pulleys if you want accurate positioning of the spindle, servo motor size also would want to be no less than 1.5Kw if you were just replacing the 1Hp you have, the problem is as the servo motors get higher Hp the RPM also drop