View Full Version : Stay with Gearbox or retro fit DC motor etc;

06-04-2013, 04:01 PM
Hi all

Still putting together my CNC conversion to my HOBBYMAT BFE 65 Milling machine. While measuring up for the motor mounts today, i asked myself a question i cannot answer myself, so here go's.

1) I have read that you can retro fit a DC motor and Controller reasonably easy to a Hobby mill,this gives you a variable speed from 0 to whatever RPM, i also read that some people don't like it, for technical reasons.

2) Some people prefer an AC motor controlled by a VFD, but i have read these are for 3 phase motors only ? does this mean i cannot do this in a domestic environment due to only having a single phase 240 volt supply?

Does anyone have any info on this, or know were i can get the info, bearing in mind i am a simple Tool maker not an electrical engineer.



John S
06-04-2013, 05:17 PM
2) AC motor controlled by a VFD has to be 3 phase however you change the wiring in the motor from star, 440v to delta, 220v , then feed this motor via a single phase input inverter that takes 240v in and spits 220v out but 3 phase.

Bit of swings and roundabout, DC motor will have more torque but generally not as reliable. AC motor is also variable but not as much torque as the DC unit unless you get physically gear it down with say a two speed belt arangement.