Cura 5 - Striations in line width on consistant wall thickness

[OPC 2]

Hi,

 

I'm having some weird problems with cura 5.1 slicing my part, I've modeled the wall thickness 3mm exactly & am using a 1.5mm nozzle. My wall settings are pretty much set to default.  but I've tried changing everything I can think of and nothing helps.

I've uploaded a few pictures of what I'm experiencing, pictures that show wall thickness, tessellation of model, and the project file which should contain all the settings.
Any help would be greatly appreciated.

Thanks!

HEPA_Stand-w-3mm-wall.3mf

[OPC 2]

I tried printing the file, and what a nightmare,  the print head repeatedly slows down and speeds up along the 2 shorter walls, leaving waves of varying thickness down the length(similar to whats shown in the slicer), I've re-set everything to default, closed and re-opened cura, changed the model wall thickness to 3.1, 2.9,... no luck.

 

print settings are 1.5mm nozzle, .5 layer thickness,

although I have a Mark2- I'm using the default UM2 ext machine profile. (with a few modifications).

i've attached some images of the printed part, & the STL .

Any help would be greatly appreciated.

0-Deg_Stand_With_WaterTank_Cutout-Combined_3mm_wall.stl

 

Edited August 1, 2022 by OPC
tried to rotate image

[OPC 2]

Here is another instance of the problem, but on a much smaller part & a completely different model.

I'm still trying to get a grasp on all of these new wall settings, but from what I understand it looks like:

some layers seem like the wall transition length is set to 100x

some layers are just jacked up

some layers are just fine.