Issues with PETG Filament Sticking to Nozzle During 3D Printing

Hello community,

I’ve been encountering an issue with my BBL PETG filament when attempting to 3D print. This filament is a fresh spool and every time I start a print, the filament ends up sticking to the nozzle and causing small bits of filament to scatter around the print bed during the printing process. I’ve tried various troubleshooting steps like adjusting temperature settings, calibrating flow rate and the K factor, changing layer thickness, adding additional dehumidifiers to the AMS, fine tunning print parameters, and cleaning the nozzle. However, I’m still having the same problem and can’t event print a benchy boat.


I’d greatly appreciate any insights or suggestions on how to resolve this issue. Thank you in advance for your assistance! :grin:

Hi, imho PETG is sticky and you are clearly printing an overhang so it wraps. Nozzle is catching that wrapped material and dragging all over the print. First of all i would change infill pattern to “not grid” like gyroid to minimize dragging. If that is not enough then slow down printing speed (set lower volumetric speed in filament settings like 8-10) and increase fan speed a bit but you really need to dial this in. In case of PETG it’s always a balance between good layer adhesion and just enough cooling to avoid wraping.

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Thank you for your response! But I don’t understand, my overhang is very gradual, and I’ve already reduced the print speed to 30 mm/s. Even first layers of a benchy boat failled. I didn’t think about changing the infill pattern and the volumetric speed, I’ll give it a try.

I also wondered if it’s possible that a newly opened spool could have some moisture, which might be causing this issue. What do you think?

And I was also wondering if it’s normal that when I directly feed the filament through the P1S interface, it loops at the nozzle’s output and sticks there?

  • Try Cubic instead of Grid, it gives a much better result with minimal “dragging” in my experience.
  • Dry your PETG particularly when new, its recommended by BL as they don’t from the factory before its vac sealed.
  • Door closed and lid on, it will work better in the warmer chamber.
  • My average speed is 100mm/s, first layer around 40-60mm/s
  • Overhang on the base layer is often touchy I find, the edge will curl up and usually catch the nozzle on the next sweep. I try to keep my bases squared off with a mild chamfer unless it can’t be avoided.

PETG is one of my favourite materials these days and I find its finicky but works well once you’ve found the sweet spot.

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I recommend trying a different PETG brand and compare results. I have had nothing but problems printing BBL PETG. There is another thread on this forum discussing PETG issues and BBL PETG. I have had far better success with Sunlu and Elegoo than BBL. I have literally tried everything to get BBL PETG to print well and not had a lot of success with it. Their PLA prints fine, but every spool of PETG from BBL that I have received prints horribly.

I’ve finaly managed to print.
I followed your advise by setting the infill to cubic, reducing the speed to a maximum 100mm/s.
I increased the flow ratio, but i’m not sure if it was the right decision.
Additionally i dried the fillamment for 8 hours in the oven at 60°C and changed the thermal grease of the hottend, which was completely dry. The change of the thermal grease was, for me, the best improvement in print quality.

Thank you all for yours advises

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