[76] Im having a problem getting Mach 3 to control the spindle on and off

If you are using the Mach3 USB controller: Make sure to watch this video: https://www.youtube.com/watch?v=Qi4M3DAtTXg If you are still having issues, make sure to confirm that you send the specific output you want to use to PORT 3. This is not mentioned in the video. If you are using OUT1 on the controller, make sure to remove that pin number from the Motor outputs (config -> ports & pins -> motor outputs) for the spindle line and set it up in the outputs (config -> ports & pins -> outputs). If you are using the Pokeys57CNC controller: Watch this video: https://www.youtube.com/watch?v=0SLFuM4tzuU