Systematic grooves and studs.

Hello, I have reprap constructed on gate/Prusa i3 design. The Z axis has integrated screw. After replacing it with the new one, there was no effect on the issue. After replacing the screw (gold one on the picture, but I have a black one - polymer made) The studs turned into the grooves. The spacing, and height of both is the same. This problem is present on different filaments (on the picture white TPU, and green PLA). Does anybody have any idea what is wrong?

higher resolution pic:
https://imgur.com/a/kXXFu

Attachment 11063Attachment 11064

The gold (brass) thing in the picture is the nut, not screw, so I'll answer based on thinking you replaced the nut.
Those bands looks very regular, it could be z wobble. Can you measure the distance between the bands and let us know what the lead on your leadscrew is? It'll be a lot easier to diagnose the issue with that information.

Hello!


Thank you for your response! I thought I will receive any notification to my email that someone has responded, it turns out I hadn't... .


Of course, on the picture I meant the nut, not the screw - sorry. Distance between the bands are 4,00 mm (0,158') and the leadscrew is trapezoidal screw T8 x 8. So, It looks like half of the lead.
But I have replaced the screw (integrated with nema stepper motor) as well as the nut from the picture and the issue is still there.

Hi Skinnyppl,

I'm Harry, I'm new to the forum.
I'm having a similar problem with my 3D printer. I was wondering what you did to constrain / reduce Z wobble?

Have you checked the alignment? The Z banding can be improved, but I would start by checking the alignment and that nothing is loose.