bad z-seam on boxes

Getting this crazy z seam on thin (1.75mm) walled boxes. Using recommended LE Cura 3.6.20 settings for nGen, High Speed (0.38mm) except set acceleration to 300mm/s2 to prevent some X/Y ringing that I was having (z-seam was similar at 100% reccomended)

Taz 6, v2.1 single extruder

Any ideas?

That’s a drastic seam. What’s your current setup/profile/etc?

Sorry, just added. Currently running recommended (LE Cura -latest/3.6.20) except the acceleration setting. Looks similar on recommended but with X/Y ringing in the walls,

High speed (0.38mm layers)

Tuned esteps (was under extruding a bit in the pics) and not much effect on seam

Try a 45deg rotation on the table (z-axis). If the seams are still there it could be the stl.

When you watch the print at that corner, does the filament extrude promptly at the corner? Or is there a delay?

Have you experimented with the Shell settings? If not, try changing the Seam Corner Preference to Hide Seam. Could also try checking Outer Before Inner Walls and see if that does the trick.

Rotating the box, moving the seam, changing the seams settings all just move the problem. You can’t see in the photos, but there is an inner seam on a different corner as well that looks the same. The seam seems the same (lol) regardless of X or Y orientation. If I do “optimize wall order” it aligns the inner/outer seams and the deformation is even more dramatic, as you would expect.

The STL mesh seems fine, as do the animated paths in CURA

Its seems there is a delay for a the first few mm. Also seems like it maybe be overextruding a bit at the end of the wall, giving the “lump” + “cavity” effect seen in the photos.

I tried to do surface mode and it totally failed, spiral(vase) mode looks flawless though, both of which make sense given the symptoms.