Re: My new mill

> just remember, that no matter what software you use, ALWAYS have an
> emergency stop button that kills the power supply/s directly, with no
> software inbetween. sure, the software can detect it too, and stop
> whatever it's doing, but the first priority is to power down those
> motors.

Yes, I second that, strongly! I built up a little circuit that connects up to
the fault relays of the servo amps, and the fault input to and servo enable
from the CNC, and also a manual e-stop chain. This thing allows the
CNC, servo amps or the operator to shut down the servos, and also
kills power to the opto-isolator module that controls spindle, coolant,
etc. In addition to commanding the servo amps to disable, it also
interrupts the main DC power supply to the servo amps, and connects
a load dump resistor to absorb any back-EMF generated by moving
motors. I put this circuit in very soon after setting the thing up, and
it has come in handy a few times. An old version of the EMC would
occasionally break the connection between the user interface and the
servo code. The machine didn't go haywire, you just had no further
control of it. That's a bad enough feeling!

Jon