I have a G0704 Mill that has a control box with a C32 board inside. I am trying to figure out how to control the spindle with mach3 using the stock Grizzly control board. From looking at the KBIC
SCR DC Motor Speed Controls, it looks very similar to the Grizzly board with the P1,P2, and P3 inputs for the potentiometer. Here is the wiring diagram from CNC4PC on how to wire the KBIC with a RJ45 conection. Looks like to me all you need to do is wire the boards alike. Any inputs? I also am wondering would I just leave the power switch on the mill ON all the time so Mach 3 can turn the spindle on and off.

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