On my Beaver Mill I put an Allen Bradley MPL-B580J motor which is 8KW 34Nm cont 87Nm Peak. It is well over powered and I dont have any need for the low range in the gearbox, I can put an 8 inch collet spanner on the collet holder and start the spindle at 1RPM and only just manage to stall it, any faster and no chance.
On the Bridgeport, which I am re-doing at the moment, I have put a F4050 Allen Bradley motor which is 6.7Nm cont torque and about 2.8Kw and although I have not really done much with it yet it seems plenty.
Hood