Trouble with Bambu PETG-CF

I am having a very hard time with Bambu PETF-CF, and it’s becoming the bane of my existence. Here is the info you need:

Printer: X1C

Filament: Bambu Lab PETG-CF Indigo

I have dried this filament two times at 65 C for 8 hours and I had the filament inside the drier running during my last print.

Here are my settings in the slicer, this is based on another thread on this form in which the person had the same type of problem. Unfortunately, it did not work for me.

Below is the result of the print with these settings.

Each time I print this filament, I get these blobs on the outer walls(?) of the print. Every. Time.

I have calibrated this filament manually, I have used the default profile, I have used a recommended profile from other users. It still happens.

Please, someone give me a glimmer of hope. I’ve had more success printing ASA than PETG-CF at this point. I’m fairly new to 3D printing so I’m figuring out things as I go.

Any help would be great, thank you.


  1. If I understood correctly, besides the shown settings and figures, you also tried using the default settings, correct? Are the results identical?

  2. Did this happen with other prints? Or is this the first print with PETG-CF?

  3. Did you calibrate the filament? At least flow and PA?

  4. I am not arguing that it isn’t dry, but be aware that the procedure may not be long enough for PETG-CF.

Note: I can print PETG-CF (different colours, including indigo blue) smoothly, with simple filament calibration and default settings.

First, thanks for printing clear photos and supplying all the information.

In all fairness, I do not see anything wrong with your settings. I checked my various filament profiles for PETG and with only slight deviations, they are well inside of what you’re doing.

To be honest. Of all the PETG filaments I’ve used, Bambu ranked last in quality and layer adhesion. Sure, flat surfaces were no problem but put anything near gravity and you have similar issues to what I see in this photo. Green arrows representing filament droop.

However, I’m wagering that the model is oriented so that gravity is probably in more the direction of the red arrow. Either way, let’s say for a moment that the filament is not at fault. Do the artifacts appear in the same place during each trial print? Also, have you tried to change the orientation of the model to see if you can duplicate the artifacts or if they location of the artifacts move as the orientation of gravity shifts?

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If you’re grasping for straws, here are some things worth trying:

Try it with gyroid rather than rectilinear infill. A lot of people have counselled that, especially with petg.

You didn’t show your Quality settings, but also worth trying is Arachne instead of classic for your wall generator.

Lastly, whatever you do, report back and let everyone know what worked and what didn’t. Then other people who share your problem will know what to do without having to initiate a duplicative posting.


I think your cooling settings are too aggressive in the settings you posted.
PETG can be very sensitive to the cooling fan.

You stated you tried printing with both the stock profile and a custom profile.
Can you post pictures of the other attempt and label which one used which settings?

Another clue here is the fact that these blobs only seem to be appearing near that overhang.

I would slow down all of your “Other layers speed” to 80 mm/s for each setting.
This is my default for PETG and this is “bullet proof” for 99% of PETG (and PETG-CF) filaments I have tried.

I just now noticed his bridging failure. So, that tells us which way was down when he printed it. That means the ripped sides he’s complaining about all occur in an overhang scenario. So, it’s something about overhangs that’s throwing it off.

It would be worth looking at your overhang settings. Here’s mine:

Screenshot 2024-03-26 132503

When you’re trying different solutions, you can cut off that part of your model in the slicer and print just that part. That will save you a lot of time and not waste as much filament while running tests.

Hi, I have been very busy the past week, I will test this and report back when I can.

Thanks for the feedback. I will be testing shortly. It’s been a crazy week for me.