hi, not sure if this is a bug, but when I first started using step files directly in Bambu Lab Studio I noticed how much smoother arc generation was, and the artefacts on circular paths were non existent. However recently I’m seeing artefacts when I slice my model on angled circular surfaces vs the same model sliced from a STL.
It has the same behaviour in ORCA slicer too.
Just a thought - what happens if you choose Classic instead of Arachne?
Under Quality > Wall Generator
No change and I have checked step file in Fusion360 and others, and it’s not the CAD model
Cheers
Mike
I opened an issue on STEP files two weeks ago, their conversion of STEP to faces is not good enough : Imported STEP curves are not always converted to smooth curves in Bambu Studio (lack of precision) · Issue #1516 · bambulab/BambuStudio · GitHub
EDIT: STEP files are not sliced, they are converted to mesh then sliced.
Thanks for that, I noticed it before but the CAD package had an issue with its new ACISs engine, so assumed it was me. It must be a coarse meshing artefact because the STL is smoother, and sadly the sliced image is what you get with the printed model.
Hope it gets sorted reasonably quickly
Mike
I use F360 and have had it mangle the hell out a few models during creation of the STL (I do 3mf now, it’s an option if you ‘Export’ instead of ‘3D Print’)
Some odd thoughts if you feel like playing with it - run the Repair Model routine and see if you get anything different, or try the Export to 3mf in Fusion. Might be something going on with the mesh …
Well the same CAD software can export into many formats, the parasolid 3D model looks fine in my software, the step and stl files export ok, and view as expected in other viewers, it is the interpretation of the step file by Bambu Studio that is the issue, I can use finer meshes in my CAD stl export, that will improve stuff, but I expect the “bug” will be getting looked as because it has been flagged already.
It’s great that the slicer preview is accurate, so any deviations seen are reflected in the 3D print. It is annoying though because the overhang quality is negatively affected by these inconsistencies 
Mike
Well, I have cheated before and 3D printed on High then used Simplify in the slicer to reduce the mesh … No one cares if you cheat … I won’t tell. 
Yeah the slicers now do a great job of showing details. They sure have come a long ways. There’s an interesting YT Vid that compares a 2012 slicer to a 2023 slicer. Kinda a fun watch.
At this point it’s really mostly polishing …! Overall it’s so much better than when I started.
Glad to hear the Bug got picked up!
Cheers!
Slicers still have a huge way to go.
Currently slicers operate more on a 2.5 D model, not really working in 3D. How cool would a slicer be if it would not be forced to strictly adhere to layers but could change z-axis much more fluid?
Stop making my brain hurt. I have trouble enough remembering all the settings in the current ones (half of which I’m not totally clear what they do) and you want 3D SLICERS?? Shame on you.
Next you’ll want 5 axis machines…
Something like this ? 
LOL! Exactly That Slicer hurts my head. Tuning it must be a b*tch!
