Quote Originally Posted by NordicCnc View Post
JAZZ, what motors are you using to drive the ball screws and is the Z-axis motor with a brake? The Z-axis for my machine will be quite the same weight.

If you read one of my last posts in the build log http://www.mycncuk.com/threads/13448...823#post114823, I wrote that I will probably use Delta 400W servo motors and with a brake on the Z-axis. Well now I've got an offer for a full return from the supplier of those JMC 180W with integrated drivers, if I swap them for JMC 400W servo motors with integrated drivers. The problem here is that those JMC 400W servo motors does not come with a brake option.
The motors are 8Nm Lichuan closed loop steppers using 230Vac mains drives. It doesn't use a break because the gantry is vertical so Z-axis isn't fighting gravity, plus 8Nm is more than enough for this Z-axis even with heavy ATC spindle on it.

Regards the JMC then I've no experience using these motors or drives so I can't comment on how good or bad they are and I haven't looked at the specs, but if I'm honest I wouldn't use motors with integrated drives on a CNC machine. The heat and vibrations from the motors along with cutting debris, esp from aluminum coolant, etc, can't help with life expectancy but for me what's worse is the fact your running long signal wires back to the controller leaving you wide open to issues with interference from noise.