I've been getting some problem layers with this filament, especially on flat pieces like this. The first layer is always good, but flat layers (top and bottom) that are not on the bed are not great, like the filament is sagging and not connecting to the lines next to it, regardless of if they are supported or not. This one was a flat layer (completely horizontal) that was fully supported with the zigzag supports from the sovol version of cura.
I know ideally I wouldn't have totally flat overhangs like this but with the piece I want to print there isn't really a way around that other than printing multiple flat parts and gluing them together.
I am using a Sovol sv06 and overture PLA. I did not have this issue with the sovol silk silver pla.
I've tried leveling my bed again and I think mu z offset is OK because the first layers look good. Currently I'm printing another temp tower and will try some other calibration pieces but any help is appreciated
In my experience this is just how 90° overhangs are. It can't be perfectly flat because if it was it would fuse to the temporary supports. You might be able to get better results with better fillament cooling (or lower fillament tempatures), but afaik some artifact will always be there. So unless I'm mistaken you can't really "fix" this issue and you are most likely better off designing around it and adding some extra tolerance when you have to use overhangs like this.
You can change the support top layer settings and mess with if there is top layers and how many there are, then adjust the gap between support top layer and the first layer of the print on top of it until it’s supported correctly and comes away easily.
I have thought of that too but I didn't have this issue with the other filament I used. The 90° overhangs were rough, but they didn't have lines falling off like with this one.
If I can't figure this out I will just re-design the piece to print in two parts and get some 3d gloop or something to stick them together