Gcode or machine issue - RESOLVED

Brand new to cnc and carbide; so I’m sorry in advance if there’s something simple I’m missing. But I may need some troubleshooting help. I just set up the basic Shapeoko 3, and am having some problems with my cuts.

I’ve set up the following Accuracy cuts for a 3 3/4 x 3 3/4 piece of particle board, with a 1.5mm bit.

But when running the job, the machine starts cutting farther to the left of where the job should start (About two inches to the left, even though I zero’d out in the lower left corner.) The machine will cut the straight lines fine, but have issues following the circles.

Each depth pass; the whole job seems to shift farther to the right. Here is the job about 40% through.

I was wanting to get through all the cuts; but I was worried my bit would snap cutting deeper each time.

The only thing that I see that may be physically wrong with the machine is the belt alignment for the Y axis. It looks like the motor is too far forward.

I’m not sure what additional info may be helpful, but here are my settings for Carbide motion, and the cut settings.

Any help would be appreciated, as I can’t wait to start getting deeper into inc machining!


First, did you watch any of the training videos?

Second, have you checked all the set screws on the pulley’s to ensure that they are on the Stepper Motor flats? (All 4 motors)

Third, the X-Axis pulley is on backwards. See how crooked the belt is? Flip the pulley.

1 Like

You need to flip the pulley around so the gears are next to the motor to get the belt lined up properly. And when you put the pulley back on the shaft, make sure one of the set screws is against the flat side of the motor shaft. You will want to check the set screws on each motor to make sure one set screw is on the flat, as that seems to be an issue on lots of the machines that come pre-assembled.

1 Like

I’ll get the pulley flipped; and then watch the training videos. I’ll admit I got excited and skipped past those. i didn’t even run the hello world. :confused:
But thanks for the replies, and for confirming my thought about the pulley. I was more just assuming it was correct since it was shipped that way.


Flipping the pulley seems to have done the trick. No more miss-alignment, and the machine is cutting like a dream. My Hello World ran ok, although my board wasn’t surfaced, and drifted towards the side.

I’ve since surfaced the wasteboard, and carved in a grid for lining parts up. Next up is cutting out a dust shoe; then set up a clamping system!