RE:
As a first step, I would clean the nozzle/hotend using a "coldpull". This can generally not do any harm if you change the filament type.
Coldpull:
wbr,
Karl
Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen.
RE:
Have you checked your hotend for a loose screw attaching it to the rails? See if you can wiggle it back/forth. 240 might be hot for some PETG.. I often print at 220. You can try that, but seems like this is something else. Looks like this happens more when the nozzle changes direction and moving quickly, so I’d look for some looseness in belts, screws clamping the bearings to rails. Just for curiosity are you using the same sheet that you use for PLA?
RE: Bad first layer Petg
The blobs may be the result of a leaking hot end. Did you change the nozzle? Can you take a picture of your hot end (without fan shroud)?
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