Using an arduino and gshield to run some bigger drivers and motors: ie nema 34

I’m using a Gecko G540 with separate drivers for each of the Y axis motors. I normally use Linuxcnc which lets me do the slaving in software but in order to try out Easel/grbl, I made up a controller using the Arduino and a cnc sheild. The cnc shield doesn’t have any drivers fitted, it was just a convenient way to get things wired up.