I print in nothing but Bambu Labs PETG-CF, sometimes with a .60, sometimes with a .40, but usually with the .60. Not every print looks fantastic but almost every print does. I mean they all look good and the vast majority look great. I just finished an 7 hours print with no blobs. In fact, I’ve never had a blob. I don’t use any whacky settings…what is different? The .40 hotend is the E3D ObXidian. I paid about $80 for it and have never regretted it ever. I’d buy the .60 if I could find one for sale, they’re all sold out. So I tried the Ali Express version with changeable CHT clone hardened nozzles. I bought a bunch of nozzles in .40 and .60. So far all I’ve used is one .60. It prints great. I print in Sport mode if I judge the model looks like it would benefit from it, long runs, etc. That entire hotend, cost about $25. With the genuine E3D Bondtech ObXidian hotends and clone interchangeable CHT hardened hotends available…I’ll never mess with an OEM hotend for anything.
Thank you everyone for all the information. I would like your opinion on my print - I usually get good top surfaces even with blobs, but it’s usually corners that have issues. (The nozzle in the pic is on my A1 mini but I get the same symptoms on my P1S)
This is after a 4 hour print, 0.4 nozzle.
The issues that you guys are talking about?
The first few layers of this print has some grid infill. Reading the posts, the most likely culprit is the crossing over of the infill lines and the “speed bumps”.
Calibrate your pressure advance?
This is not a pressure advance issue, the shorter prints are fine and the bottoms of the big prints are also fine.
In my limited experience pressure advance mostly affects corners, where the nozzle is decelerating and accelerating.
Good luck figuring out your problem.
A too-high k value would leave a similar artefact but you would see it through the whole height of the edge.
I was printing a part with Bambu PETG-CF. There were a few sections where I made a 45° angle to support an overhang. There were strands on the bottom of the 45° angle and in the end I noticed some PETG-CF stuck to the nozzle. Enough that if the print was bigger, it could have been a problem.
Correction: I used an equal distance Chamfer and the walls weren’t perpendicular, so it was actually a 35° angle.
I adjusted the angle to 55° and printed it again. There were no strands this time and the PETG-CF didn’t accumulate on the nozzle.
Maybe part of the solution is designing the part to be less challenging from a 3D printer point of view. So no crossing infill or bridging or overhangs for long prints and using steeper angles. The strands and crossing infills seem to be the direct cause of the blobs and larger accumulation of PETG-CF on the nozzle. Which are in turn the cause of all the other defects. I think PETG is just too sticky to deal with strands and crossing infills.
That might be the main difference between those that have problems and the people that have had good experiences, their prints didn’t have crossing infills or significant bridging, overhangs or low slopes on the bottom edges.
I fed all this into Chat GPT and asked for a boil down of successful parameters.
Based on the discussions and contributions in the post, here are the successful print settings for Bambu PETG-CF using a .6mm nozzle, as compiled from various users’ experiences:
General Settings:
- Nozzle Diameter: 0.6mm (some users also reported success with 0.4mm, but 0.6mm is recommended for better results)
- Layer Height: 0.24mm (can vary based on specific requirements, but this is a common setting)
- Print Speed: 100 mm/s (may vary, but generally lower speeds help with print quality)
- Infill Type: Rectilinear or Gyroid
- Infill Percentage: 15-20%
- Wall Settings:
- Number of Walls: 2
- Wall Order: Outer walls first
- Inner/Outer Wall Speed: Match speeds, typically 80-120 mm/s
Temperature and Cooling:
- Nozzle Temperature: 250-260°C (with some users going up to 270°C)
- Bed Temperature: 80°C
- Part Cooling Fan:
- Minimum: 40% (after 20 seconds layer time)
- Maximum: 90% (after 6 seconds layer time)
- Chamber Fan: 70% (adjust based on ambient conditions and print size)
- Auxiliary Fan: 0-30% (varies based on layer time and print complexity)
Retraction Settings:
- Retraction Distance: 2mm (some users recommend up to 5mm)
- Retraction Speed: 40 mm/s (can vary, but faster retraction speeds may help reduce blobs)
- Z-Hop: 0.4mm (can disable if not necessary)
Special Considerations:
- Filament Drying: 65-70°C for 8-12 hours before use
- Flow Ratio: Adjusted to around 0.94-0.96 (some users suggest even lower, around 0.89)
- G-code Addition: Some users suggest adding
G29.1 Z0.03at the end of the Filament Start Gcode for fine-tuning
These settings are not definitive but reflect the collective experience of users who have had success with Bambu PETG-CF filament. Fine-tuning may still be necessary based on specific printer conditions and print requirements.
I know this is a bit old but I just wanted to say thanks for your settings! I was having trouble getting this filament tuned but once I entered these settings I was able to get it tuned and printing almost as good as regular PLA. Thanks!
Ciao, utilizzo una X1C per lavoro e stampo esclusivamente PETG-CF
in questi mesi ho utilizzato circa 20 bobine di Bambu PETG-CF e non ho mai avuto problemi, tutte le stampe sempre perfette !!
Circa le macchie bianche sul primo layer ho risolto applicando un pò di colla bambu
I parametri utilizzati sono quelli di default di bambu studio
Qualche volta ho utilizzato PETG-CF (no bambu) anche in questi casi ottime stampe anche se ho dovuto correggere leggermente la temperatura di stampa.