Using X and A for dual motor gantry

[blallen62]

Hi, how do I go about using the A axis as my second motor on a dual motor gantry setup on the X axis? I'd like to be able to home the two motors independently in order to square the gantry automatically.

[tpaszkiewicz]

I would also love to get an answer. I'm struggling with it for days. For now, i have two motors on one pin but it's impossible to easily square the gantry, as @blallen62 said. @dguerizec can we ask for advice? thank you

[dguerizec]

Well, grbl is not designed to do this alone.
For double axis homing, you'd have to use an external program, but I don't know any that works with grbl.
I now personally use linuxcnc to control my CNC and grbl is only for my 3 axis, 3 steppers laser engraver.

[blallen62]

Since originally starting this thread I've just given up on dual axis with grbl. I just have a single pin on the mega tied to two stepper drivers. I square it every once in a while manually and have $1=255. It's good enough for what I'm doing now.