First layer missing on parts with rotation about Z
Hello,
I've run into something strange when slicing a model. To preface the situation, I've just updated to PrusaSlicer 2.9.4 on a Windows11 computer and printing on a Mk2.5S. When I sliced this particular model which has 5 parts (with no rotation with respect to its original orientation), I noticed that the first layer for one of the 5 parts was missing. As I rotate the model about Z, different parts are missing the first layer depending on the rotation angle. So for example in the image below, I've setup 4 copies of the model and rotated it about Z in increments of 45 degrees starting with 0 degrees on the left. When looking at the file in a CAD program, I don't see any layer height issues based on the parts within the model. Has anybody else seen an issue like this before when slicing a multi-part model? I've attached the model file for reference.
RE: First layer missing on parts with rotation about Z
The only way that I can picture this happening is if the angular orientation of the model with respect to Z is off by some minor degree amount, and that this effect is just how Slicer is interpreting that situation.