Do I have my motors in the correct orientation?

So I’ve put together my MPCNC but I am not having any luck getting the gcode to work. I am using AutoCad Fusion 360 CAD and CAM with the MPCNC_Fusion360_V10_SDcard.cps post. I was talking to one of the CNC operators at work and from our conversation I think maybe one set of my motors are backward.

When looking at my machine from the front. X travels back to front, positive to the back. Y travels left to right, positive to the left. And Z travels up and down positive to the up. Are these correct? Or do I have something backward?


That feels rotated to me (I prefer x to right, y back) but it’s still a right handed coordinate system, so it should be fine.

If you don’t know the right handed coordinate system, then you should look it up. I was going to try to describe it, but I’m sure someone has a good picture.

1 Like

Thanks, you opened my eyes to new problems that I’ll address in a new post.

There is test gcode at the end of this page.

Hey Matt, thanks for the reply. The crown with ESTL was one of the first things I made after the machine was running. Funny story… Unfortunately, since it seemed to draw fine I wasn’t prompted into checking scale. I am new to all of this, so measuring the final product was the last thing on my newb-elated mind. lol It wasn’t until I clamped some stock into the machine and came back to find my clamps being milled that I realized there was a problem. lol The chinese company that sent me my T16 gears actually sent me T20. Thankfully problem solved with a mod of the firmware.

My problem really right now is understanding how the coordinate systems in the model, CAM, and physical space all relate to each other. i.e. In physical space should X travel left to right from the front or should Y? Should Y be depth or should Z be depth. In model should X,Y, Z match physical space? Should CAM match the Model? All quite confusing. Jeff’s post helped a lot with that.

X should travel from left to right from the front. Y should travel from front to back. Z should travel up and down. The X, Y & Z in your model should match this, as should the CAM model. If your MPCNC doesn’t move like that in R-H you might have the stepper wiring backwards, driving things the wrong way.

To add a bit to that, the origin or axis in your models don’t mean anything outside of your CAD software, the CAM and Machine are tied together though.

A part made in CAD can be rotated in your CAM and given new axis and origins (work offsets, different starting points).

Take it slow and work through a few of my tutorials and it should start to make more sense. Keep asking questions if you get stuck. There is a learning curve but once you get it it is amazingly powerful.