I am considering getting an 8 x 32 knee mill (Jet JVM836 or Grizzly 6760) first to use as a manual mill, with future cnc conversion. can't deal with a full Bridgeport in my space. My concern is the limited spindle speed range of the step pulleys - usually from about 200-11800 rpm).

Could anyone hazard a guess if the head and bearings would take spindle around 3000 rpm? Has anyone done a conversion on same either by chnaging the step pulleys, or better yet, by switching to either a dc drive with motor controller; or using a 3 phase ac motor and variable frequency drive?

Thanks,

Chris Krumm