Shifting on X axis

[anakaine (Simon)]

The following two images show a battle that ive been fighting with my blue and white chinese frankenlaser for quite a while now, but im not wntirely sure whats causing them.

Periodically the laser seems to lose its place - not recognising what step or rotation etc that its on.

It is not belt related. I have new belts, new motors and new pulleys. The issue predates these, and everything is tensioned.

I can only think of a few things:

• Loose or damaged wiring between stepper and controller.
• Stepper motor controller has issues
• Ruida controller 6432G has issues (this issue seems be become exacerbated the more complex the job is, both when sending from PC and when actioning from controller - so could be memory issue).
• The belt could temporarily be slipping up on the edge of the captive roller inside the gantry, which would somewhat explain the ocassional but incremental offset.

[thelmuth (Tim Helmuth)]

Check out this resource. It looks like it may be the PWM Edge Rising issue.

How do I fix skewed or slanted engraving?

This is an example of a fill followed by a cut around the letter A: [image] The fill is slanted, but the cut appears to be correct. If you have engraving that is slanting to one side, but cuts appear correctly, you likely have your motor pulse step polarity set incorrectly. On Ruida controllers, there’s a setting called ‘PWM Rising Edge Valid’ that you can change for each axis that tells the controller whether the rising edge or falling edge of a step pulse is what the motor driver is lookin…

[jkwilborn (Jack Wilborn)]

Looks mechanical, such as a loose grub screw.

It jumps out of alignment, then returns back to alignment, it would seem to indicate a loose pulley or drive shaft somewhere.

It doesn’t really appear to be a pwm rising/falling issue from it’s appearance.

The pwm rising/falling is easy to change to see if it fixes the issue.

I think it’s mechanical.

[anakaine (Simon)]

I can confirm its not the rising edge pwm issue.

I am not sure, but I believe I have found the culprit. And well, check the attached.

This machine has been an absolute adventure.

[anakaine (Simon)]

Ive now fixed the bracket and rising idler pulley issue. On to the next problem, which looks suprisingly like the first image in this post.

Absolutely maddening machine!