You are saying the lighting of the room disturbs flow calibration?
It does, at least with the textured plate. Also Bambu says that, one of the reasons of the minimalistic LED light in the printer.
2 Likes
Sure it does, I happen to me one time (I never do autocalibration usually) I forrget to uncheck and had my LED ring on, the print was a disaster. Auto-calibration does not work when over lighting.
3 Likes
It would be nice if Bambu would offer a solution for that - integrating a prober light, but turns off while calibration - or give us a 24V oder 12V, or even better a Neopixel 5V Port to set proper light, but again - turning automatically off during the calibration. =)
So how do you tune then PA? Setting the K value in start gcode?
2 Likes
It would be nice if Bambu would offer a solution for that - integrating a prober light, but turns off while calibration - or give us a 24V oder 12V, or even better a Neopixel 5V Port to set proper light, but again - turning automatically off during the calibration. =)
Sure and also for the camera, using external light does not make the image brighter because the camera adjuste its exposure once, if I start printer with external light and then set it off external ligth , the camera dont redo its exposure and the image get black…
So how do you tune then PA? Setting the K value in start gcode?
Yes, and depending on my prints result, I do adjust this value
M106 P3 S51 ; turn on chamber fan 20%
M900 K0.018 L1000 M10 ; Set linear advance to 0.018
Only K factor need to be changed
EDIT :
- too much plastic on borders then increase PA a little
- not enough decrease a little
- good result let it as it
No need to do a full calibration process for each filamament, it is a waste of time, start with 0.018 for PLA and adjust, the good value is not far from 0.018 for PLA
This is true for all settings, it is better to learn to adjust setting by viewing results of yours prints rather than doing tons of calibration process…
The SoftFever fork of Bambu Studio offers two variations of PA test and lets you specify the value in the filament profile. My own testing ended up with a value of 0.22, but 0.18 would also be in-range from my tests.
2 Likes
I tryied both softfeaver calibration and find different results for the same filament, that’s also why I prefer to rely on my own print results, and after all what I am interrested in are my prints quality not calibration objects quality 
So… For best results, should we be running our X1C’s in the dark?
1 Like
Yes, at least for auto flow calibration.
@holmes4 I need to look into this Slicer.
I would prefer setting PA for each Filament, because also different colors have different PA values. I’m anyway used to do it manually with all the Vorons. 
2 Likes
Ok, it seems it is not that simple!
While @rovster seems to have nailed it, it might not be the only issue.
I reprinted the cube with auto calibration when room lights were turned off. Issues are still there! I even turned off the LEDs of the printer but seems that they are turned on automatically.
11)PETG, profile “0.16mm optimal @ BBL X1C”, Temperature increased to 270°C, room lights were turned off to ensure auto calibration is not disturbed.
I give up and will create a support ticket!
4 Likes
Once you figure it out, please do let us know what the cause was.
Yes, of course! Would be interesting to see similar prints from other users. I already noticed the phenomenon before I designed this test cube. Basically you should find the issues as long as you have some holes.
Here is the first print I ever did with PETG.
The bottom one was printed with an ultimaker original with PLA. The top one is printed with X1CC and the same material I have used for all test prints in this thread.
1 Like
Did you also try another PETG with the Bambu?
€: Just noticed, if you turn the LED off, it will be automatically turned on after the calibration if timelaps is activated.
Seems like it’s worth a try. The prusament petg appears to have a print temperature around 230-240C (PETG | Prusa Knowledge Base), whereas sunlu petg has a higher range of 235-250C. IIRC, the “generic petg” bambulab slicer setting assumes 250C.
It’s either that or there’s something wrong with T_guttata’s machine that Bambulab QC didn’t detect but maybe should have.
Yeah, I had to add a blower fan to my S1 to get it to work right. The air has to move to move the water away.
1 Like
The orientation in the image does not match with the printing direction (its reversed 180°). What you see is:
- The artefacts are visible on all 8 holes.
- The layers affected are those to finish the wholes
- The artefacts are always in the same layers and at the same position (after the whole in printing direction, see red in the screenshot).
What I really do not understand: Why should a bad flow calibration only affect very few layers? In the image from @rovster you clearly see that many layers are affected. This is not case in some of my examples.
And just to proove its not the filament, here is an image of a black PETG print:
2 Likes
Is the black filament Prusament or something else? It may be a longshot, but do you get the same artifacts if you don’t use the AMS but instead load directly from the spool holder on the back of the machine? The reason I ask is that I’ve read that in some cases the Prusament spool can be a bit wider than the the AMS can comfortably handle.
BTW, nice photographs!
1 Like
90% of my prints are made of PETG, and I never had such a problem. Also, I cannot understand what the hype about drying filament is all about. I never did that, and I use spools that are literally years old, sitting on a shelf in the basement of my house, without any protection.
For reference, I took a silver PETG (from goedis, cheap stuff) I openend in March 2020, it’s about 3 years old. I then printed your cube with all settings standard (generic PETG, 0.20 Standard) with flow calibration turned on:
There are clearly some imperfections, but nothing I would worry about, and nothing close to what you are seeing. Either you messed up some settings, or there is something wrong with your printer.
2 Likes
@ NeverDie
The black filament is also from Prusa. Exactly because some prusa filament rolls are out of tolerance, it does not work with the AMS. In my case the black spool works and the grey spool does not. That’s why everything grey was printed without AMS and the black was printed with AMS.
The images are made with a (cheap) digital microscope.
@ skyme
For some wholes you see similar artefacts. But in comparison to my prints, not all holes are affected and the effect is far less pronounced. I would not have started this thread if I had your results.
2 Likes