I'm printing stacked Prusa COVID-19 face shields on a modded Ender 3. It works fairly well until the second layer of masks, where we get this weird effect that's kind of like stringing. It looks like the curve is becoming "low poly." I'm sorry that I can't be more specific, but I really don't know how to describe it more than this. Please look at the pictures to get more info.
One of the strangest things is that it worked earlier with the same slicer and the same profile. I am using PrusaSlicer, but I tried it with Cura and it still didn't work. There are a few more problems with the prints: some under-extrusion on the supports, and some spots had little gaps between the layers.
Does anyone have any fixes for any of these problems? I would mainly like to know about the strange kind of stringing because that actually prevents me from stacking prints.
I am printing Overture PETG at 240 on the nozzle and 80 on the bed. This is at a speed of 50 mm per second. I have the Basaraba Innovations direct drive mod, the Creality silent board with TH3D Unified Firmware based on Marlin 1.1.9, and the EZABL Pro.