aligned seam

[waterbornewarrio]

I haven't been able to get an aligned seam on my parts with S3D. (In PrusaSlicer, Seam / Seam position Aligned does the trick.) However, I recently did, but apparently some setting or combination of settings has changed. I've gone through the gcode file line by line and matched up the settings, but it still won't align. Screen shots show the desired result on top, and the typical result on the bottom (same model). Any ideas?

[gearsawe]

Move you part back toward the back of the bed some or to the left some. Is your seam position at 0,0? Think you are right at that point where the points at the back are closer and some in the front closer.

Hard to help without the file.

[waterbornewarrio]

Move you part back toward the back of the bed some or to the left some.

That does it! The model can't be centered. Moving it even 0.01mm from center (X or Y) forces it to choose an edge. This seems similar to my previous post, raft top layer orientation, where model positioning needs to be used to achieve a specific slicing result, versus control via settings...