What's causing this printing problem?
I am hoping that someone with more experience will help identify what is causing this problem on my prints.
It seems to occur more on prints with bigger rectangular bases, some smaller more intricate prints have come out ok. Most of the print is fine then I get this blobby part usually quite early on in the print, maybe it is build up on the nozzle coming off? I just dont know.
I have an i3MK3s with a quite recently fitted E3D Nozzle X 0.35mm and I'm printing a newly opened reel of Eryone PETG.
RE: What's causing this printing problem?
In looking closely at your photo, it appears that there's some discoloration and some mechanical damage to the upper layers of the print.
The discoloration may indeed be from some scorched filament blobs landing on the print, and the mechanical damage may be from the blob(s) being yanked away from the print.
I've gotten into the habit of brushing off the nozzle before most prints. This will get rid of any of the residual 'worm' and ooze and any blobs that have accumulated on or near the nozzle.
I've also found that PETg seems to be more prone to stringing and blobbing than ABS or PLA.