@Adam_Steinmark So I started on a tank for the rocket 2 hours ago so it isn’t the same CAD from before and am running it at about 90%. It looks perfect almost.
Perhaps it could be gcode like you said or the previous CAD was bad?
It looks like the layers that have this problem are in line with a feature that might require higher acceleration tolerance. I’m not sure how that would map to a deformation on a delta, however.
It is unlikely but possible. Issues like that usually don’t show up as a single horizontal stripe.
I would look at the slicer code layer by layer. unless the side we can’t see is sticking out I don’t see how this could be loose belts. This looks like a model or slicer problem.