Vertical shells print with inaccurate dimensions  

Vertical shells print with inaccurate dimensions

Hi there!

First post here 🙂

I have noticed an issue where vertical shells, especially when printing thin walls, come out with a slight and very consequent dimensional offset (for lack of a better description). There are two examples in the images:

1. The first is a bell (thingiverse) that prints very well but it is easy to see the the mid part where the outer (and inner) radius of the external perimeter is off. The model has a completely smooth profile so nothing there. I also attached an image from prusaslicer because I noticed that this happens exactly where slicer transitions from gap fill between the ext. perimeters to some kind of internal perimeter fill where the "belt" is visible. The correct radius of the outer perimeters is immediately restored once gap fill is used again.
2. The second example is a small enclosure I printed. This time the issue arise around a feature (the hole), where again the shell dimension gets slightly shrunk. I've noticed this a couple of times when printing boxes.

I don't think this is hardware related because the dimension is perfectly restored after the problematic layers (feature or different shell fill), but I could be wrong.

Any hints on how to fix this behavior is greatly appreciated. Thanks!