Spindle Direction Reversal, How To

[TacPyro]

How do I reverse the spindle direction in Mach3 mill. Currently the spindle is rotating from left to right when looking at the spindle from the front of the machine. I don't have any tooling that can take advantage of this, so I am assuming that the spindle direction is switchable.
Thanks for the help.

[TOTALLYRC]

If the spindle has a dc motor, just revers the pos and neg wires.
If it is 3 phase ac, just reverse any 2 leads. This is assuming that you are using M03 to turn the spindle on and off with the g code.
I would change the way the spindle is wired as it will make programing the same from machine to machine and program to program. This all assumes that the motor is setup to reverse direction from mach3 using the m03 and m04 commands.

[Al_The_Man]

If it is a single phase motor, Capacitor start, you will have to have access to the start windings and reverse them by relay if using M3/M4.
This pair is usually connected to the Capacitor and the neutral.
If you have a 3 phase VFD, there are FWD/REV terminals on the unit.
Al.

[TacPyro]

Update: the pinouts for M3 and M4 were reversed per the XML setup file. Now the spindle works perfectly.