XXL Y-Axis Issue

I was using my XXL this morning, and all was fine, right up until the completion of the job… Once the job finished, I powered-down the spindle, and was releasing the clamps for my piece as the gantry moved to the rear of the machine.

It was then that the issue occurred - for some reason the RHS y motor reached the end of it’s travel, but the LHS motor was still trying to move rearward… the belt sounded like it was grinding, so I immediately powered the entire machine down.

I moved the gantry forward slightly, powered everything back up, and started the homing process through CM… immediately the LHS y axis motor sounded ‘funky’ (as if the belt was trying to skip), and as if the gantry was out of alignment.

I slackened-off the y-axis belts, checked the gantry for square, and all was good… tightened the belts back up, went back through the homing process… same problem.

Any ideas on what might be causing this issue, and/or any possible remedies to the problem?

Please check to see if the Y-axis motors are still moving in synch and in the proper directions.

Please check the wiring as well.

Possible causes of this sort of thing:

  • broken wire
  • stepper driver
  • circuitry responsible for micro-stepping

if reviewing the wiring doesn’t address this, contact support@carbide3d.com and we’ll help you sort it out.


Will, you’re a genius.

The Y2 connector that runs and connects behind the gantry had come (mostly) apart, so (I’m guessing) it must have been sending an intermittent signal.

Pushing that connector firmly back together has resolved my “issue”.

Thanks for your prompt (and accurate!) help/reply! :wink:


Shouldn’t the limiter switch (if installed) automatically stop it when it hit the switch? When I built my S3 last weekend, I did an initial setup wrong and the gantry went all the way back and slammed against the back rail. This broke off one of the tabs on the limiter switch. This bothered me because I thought the limiter switch should have stopped the machine from moving once the switch was engaged. But I made the assumption that I had not put the switch on properly or had not tightened it adequately.

Since we only have switches at one corner we don’t enable them as limit switches, instead they’re used to allow us to enable “soft limits” which require the machine to calculate when it’s going out of bounds.

If you want hard limit switches you’ll need to source additional N.O. switches and wire them in parallel w/ the current set.

The limit switch is located on the RHS of the machine. In my case, the RHS stepper motor obviously wasn’t moving far enough back to reach the limit switch (because the motor connector was loose), so the LHS motor (under “full power”) was hitting the rear of the gantry, and trying to keep on truckin’!

As an aside - here’s pic of the Batman fidget spinner that I was messing around with and had just finished cutting-out for my daughter! (material: off-cut of bamboo flooring!)