Prints Suddenly Failing - Looking for Advice
I tried to print something today, and it failed. Extrusion looks very thin, and doesn't want to adhere to the plate - i wind up with a bird's nest and blob on the nozzle. I did 2 cold pulls, re-set the PINDA probe, recalibrated everything, cleaned the plate with acetone and IPA. No effect. I needed to set the first layer at -0.600 mm, which seems excessive. Thinking back, the last print I made, which was essentially a cup, had some weird issues, there were some spots that looked burned, and there were two random blobs of resin on the print bed. Last print and this one were with Pruas PETG, the orange stuff that comes with the printer, but it behaves the same way with Hatchbox PLA.
Any thoughts as to what may be wrong are appreciated.
RE: Prints Suddenly Failing - Looking for Advice
Those cold pulls, do they look normal with an almost perfect conical tip ?. If the tips are distorted or totally blunt maybe there’s a partial clog in the nozzle,
If you have a new spare nozzle at hand, it might be worth to install it and see if the issue disappears.
RE: Prints Suddenly Failing - Looking for Advice
It does sound indeed like it could be a partial clog. So it would be important to see if the cold pull tip looks proper and clean as stated by Artur5.
One could also try more tension on the extruder idler, in case your filaments are slipping.
If you print a small cube or something (maybe 1cm3), how does the top layer look like? Is there clear underextrusion visible? If it is a partial clogg, not only your 1st layer should be underextruded. If the top layer looks perfect and the sides look ok too, then you do have probably a 1st layer calibration problem.
Mk3s MMU2s, Voron 0.1, Voron 2.4
You can go as low as -2.0mm before adjusting anything else, don't do anything drastic until you have exhausted the Z calibration options.
Cheerio,
RE: Prints Suddenly Failing - Looking for Advice
needed to set the first layer at -0.600 mm, which seems excessive.
Nowhere near excessive. Absolute numbers don't mean anything but I try to set my PINDA probe so that I have a nice live Z at around -1.ooo using so that I have plenty of wiggle room up and down when I change sheets and filaments.
Also, when you print PLA after printing PETG, make sure you load the PLA at PETG temperature and do a few purges or use cleaning filament or you may end up with partial clogs due to PETG residues in the hotend.
RE: Prints Suddenly Failing - Looking for Advice
Here are some pics of a pull I did today, does this look OK? this one actually looks conical, the previous two had a sort of rounded tip, with the tip of the nozzle hole on the end.
Shot from side:
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Shot of tip:
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Whole pull - is the bulge at the top a concern?
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RE: Prints Suddenly Failing - Looking for Advice
If I remember correctly the bulge is fine. It might be more helpful if you include a picture of a first layer test print.
This is the one I like to use when I'm trying to dial in Live Z