Y axis stuck occationally


I setup X-carve yesterday. Went through the calibration procedure. Everything looks fine, except that the Y axis has some hiccups. Every once in a while, it makes a horrible sound like something gets stuck. However, there is nothing I can see that obstructs the motion.
The two straps are nicely tight and make the sound of a guitar string :smile:
The wheels along the Y drive do not turn freely.
Here is a movie that demonstrates the problem:

Any ideas?



Your belt and/or v-wheels may be over tightened. The belts don’t need a ton of tension, but just enough (I know super helpful right!). When I first set mine up I had over tightened everything!

Did you try turning up the power on the gshied for the Y steppers? (just a tiny bit)

Should the V-wheel turn or not? When the motor is not engaged, right now I set it (as the instructions suggested) such that they don’t turn.
As for the belt. I felt that after I increased the tension, things improved a bit, so I kept it tighter.

Increasing the current for motors might help. I didn’t think about that.

Is the noise happening at or near the same location every time? Any chance your wiring on your Y plates is interfering with the drag chain?

I had a cable tie stub on my drag chain (left my spindle power lines outside, and just cable-tied them to the chain, anticipating an upgrade eventually) rotated so it was hitting my wiring (my wires all have soldered spades to the terminal blocks, so they’re pretty rigid) like a card in in bicycle wheel spokes as they went by. Felt a right idiot when I figured it out…

The v-wheels should just tight enough that the don’t slip on the rail while turned, meaning that when you turn them by hand the carriage moves. Excess belt tension can out extra strain on the steppers which can cause lost steps. Tweaking the stepper pots should help though.

It was getting stuck mostly at the same location, but I can’t see any obvious wiring issue that could have caused this.
I tweaked the stepper current. I think it helped. I’ll run a couple more jobs to be sure.
Thanks for the help!

Good Luck!!

Hard to tell exactly but it does sound like the steppers are stalling from a lack of power. If you jog the Y axis more than a half inch at a time does it do the same thing? If you jog the axis 4-5 inches at a time and apply a slight back pressure to the maker slide you should be able to make it worse if it’s a lack of power. I did also find that the difference between too tight and too lose on the V wheels was a very small amount. If you don’t have a multi meter to check the power your applying to the steppers now is the time to get one. Everyone needs a good excuse to buy a new tool right : )


The problem persist. Or at least, printing a circle results in an ellipse.
How much power should I apply on the steppers?

There is a section in this link that describes how to adjust the power to your steppers.

GRBL Github

OK. I had some good progress.
Motor get enough juice. That doesn’t seem to be the problem.
However, I can sometimes see that one side of the Y axis moves slightly more than the other.
I think I was able to link this to some not fully tighten self taping screws on the side.
Cuts definitely look more circular now.