Is this banding?

[Netwrok]

I have been looking into this issue for about a month now…

Some background:

I was running Cura 14, made an upgrade to a metal bed support from plexi on my Hictop I3

Also added a metal tensioner to the mk8 extruder.

Prints working fine after putting it all back together.

Then I upgraded to Cura to the 15.0.4 and now I get this weirdness.

It looks like banding but the consistency is based on how my material is laid down and not by any movement that I can tell.

Things I’ve tried:
Releveled the whole thing
Greased the screws and nut for the up/down motion (z axis?) which are integrated into the stepper motor

Monitored heat (Stays within 3C of desired temp)

Updated again to the latest Cura (would have rolled back but couldn’t find an old version)

Any other ideas/solutions?

This one shows the motor mount and some dremel cut away due to the new bed.

I had a 80mm build platform due to the metal bed frame that wouldn’t clear the rear motor mount.

This was first print I had an issue with after the upgrades.

Worked fine until i changed Cura version.

[SOC3D]

That hictop has lead screws vs threaded rods yes? It looks like classic lead screw waves. Can you add a photo of the printer and of the z axis couplers top and bottom as well as the x axis carriages left and right.

[SOC3D]

Also, spin one z axis rod a quarter turn but not the other and try a print.

[Netwrok]

I tried that adjustment but no good.

Here is a pic of the threaded rod stepper motor

[Netwrok]

Forgot to mention I have had it for 2 years now if that makes any difference.