Cutting path incorrect -- Driver problems?

Hey everyone,

I have recently been having a problem with my machine recently, this was after a move, so consider that the machine was reassembled and this was the first carve since that assembly and a downtime of a few months.

The images attached really tell the tale, the carve goes off path often, the resulting carve is drastic from the one sent to the machine, and overall is returning bad results. This has happened with g-code exported from Fusion 360, an app from Easel, and the test carve.

Some things I have done is check all the wiring, all the pulley’s, all the hardware, the distance the motors step (A ruler and jogging the machine around) re-flashed the Arduino, updated gbrl to 1.1, un-updated gbrl to 1.0.

This has been a frustrating few days trying to diagnose the problem, the test board is covered with failed carves. I hope someone can help me resolve this problem! I am also considering biting the bullet and updating the machine to the new X-controller. Let me know if the upgrade is worth it!

Machine specifics:

Have you calibrated your stepper drivers? Not overheating, causing lost steps?
Underpowered => lost steps
Overpowered => lost steps

Dude ur belts and pulleys need attention baaaad. Or ur cutting waaaaaay too fast.
That kinda wandering is usually a loose pulley or belts.
Other option is step per mm but it’s very unlikely cuz that only really affects the size accuracy.

Looks like loose v wheels. You have slop, grab your spindle, can you rock it? X carrage? Y plates?
And clean off the fuzzys to get a better view ( or down cut bit )

Wandering off path = lost steps (symptom)
Finding the disease is now the issue.

As I mentioned earlier, what are your stepper drivers adjusted at? (Voltage @ Potmeters)
I had a Nema17 on my Z some time ago (ACME rod/Delrin block) and it was so low on friction the spindle would drop when machine was unpowered. This caused to deep cut => X/Y lost steps.

Hi all, thanks for the responses.

I have worked through a few things. First, I re-calibrated the machine from scratch. Tightened all the V-wheels, all the belts, and tuned the motor currents. I checked the steps of the axis (ruler and commands) and the axis are moving the correct distances.

I am currently running the test carve again and damn, it’s working much better. It turns out the months of neglect and the move loosened things up far more than expected.

Thank you everyone who has posted. I never took the time to calibrate the pots fully till Harold’s comment, thank you. Phil, I am also looking into Nema 23’s, as I have been but have not had the time to purchase. A machine like this would not be possible without a vibrant, knowledgeable, and helpful community, so thank you all!

For reference, the settings in the above images are 30 in/min, 9 in/min plunge, .028in depth. The plunge I usually have at 7 in/min due to the 17’s. Also I had an upcut spiral and needed a downcut, hence the fuzzies.