I’m trying to print PETG on my Prusa I3 MK2 for the first time (having already printed in PLA happily). However, the MK2 doesn’t seem to be extruding the filament while printing. I can push it through manually, and if I preheat and activate the “Load filament option”, it will flow, but not while I’m trying to do a print. I’ve been using the PET profile supplied by http://prusaprinters.com for slic3r. Any suggestions from those who have successfully printed in PETG on a MK2? Thank you.
What temperature are you printing at and what brand?
The brand is MG Chemicals. The filament is clear (no tint).
I’ve tried at 240C and 250C.
I just tried it at 220C (the last temp I tried printing at). Again, nothing extruding and the extruder temperature didn’t move more than a degree from 220. It was certainly worth checking.
What brand of filament? I bought some esun petg and it would jam instantly. Moving to a titan extruder and some matchbox petg solved it for me
@Logan brand is MG Chemicals.
Maybe try an atomic pull to try and clean the nozzle out.
Two observations:
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When the extruder is still hot, I can push the filament through manually with my fingers.
I did this after immediately after the last failed print attempt.
Are my dry skinny programmer fingers able to exert more force than a stepper motor with a hob? I’m not the first guy you’d chose to hold onto your wrist when you were dangling over a cliff
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If I preheat, I can use the “load filament” option to extrude some filament.
This suggests that the stepper motor isn’t grinding the filament. I have unloaded the filament a few times in this exercise and seen marks where hob cut into the filament but nothing to suggest grinding.
Both of the above suggest (but do not prove conclusively) the problem isn’t a diameter of filament issue.
It sounds like a jam to me
I’ll give that a try tonight. Thank you!
And the pronterface suggestion saves the day!
With the pronterface and the use of an indelible marker, I was able to see that the stepper motor was turning as it should, but the hob wasn’t. The set screw had come loose. Tightened it up and things are extruding. Locktite a good idea on that set screw?
Thank you all!