So I just got the H2S as my 1st 3D printer, I made this first Benchy (added the Benchy from “Add Primitive” not included one) and saw a few artifacts (each circled in red). Those seem to appear when the print head slows down to then speed up like we can see in the slicer. I also checked flow and the follow indeed increases when it speeds up. So I guess I could slow down all the walls down from 60mm/s to 30mm/s, hence removing the speed variations but it also would up the print time drastically on some parts. So is there a better than just slowing down all the walls to avoid speed changes ?
I used 0.4mm nozzle with 0.12mm layer height matte PLA all default settings, thanks.
Since your issues are near the corners, it could be and issue with pressure advance.
Have you calibrated the filament for pressure advance? The slicer defaults will usually give you an acceptable print, but if you want/expect more, you need to calibrate your filament. Slowing down the outer walls may also help.
You need to make sure your filament is dry before doing the calibration. Do not assume it is dry because you just took it out of the plastic shrink wrap.
No I haven’t calibrated the filament for “pressure advance”, but what is is exactly ? Is it something you do by hand or something you can tell the printer to calibrate ?
I will also try drying the filament to avoid any issue that could be related to this.
It is not always necessary but if you are having print quality issues it is something that may help. Many people have found the ‘automatic calibration’ is not as good as a manual calibration.
Hi, so I’ve reduced down to 30mm/s on outer walls & used the precise wall feature too to see how it would affect surface quality. Like I excepted precise wall made surface finish good but I had some very very tiny under extrusion in some places. And for the outer wall being slowed down it helped reduce the artifacts I’ve shown before quite significantly, at least 50% less visible but still present. I won’t make pictures again but I traced red lines where the artifacts appeared. I dried the filament at 55C° for 2h (Didn’t had time to do the full 8h) and I ran the automatic flow calibration. I also check the Bambu Lab Academy before doing anything else.
I ran manual flow dynamics calibration too an I will do a new Benchy with all default settings of the 0.12mm layer height this time so now precise wall or wall speed slow down. It’s not done printing but already I can see that I have the same artifact here.
It will not hurt to perform the flow rate calibration also. It should help with the under extrusion. The next things to work on are accelerations and possibly retraction settings.
Keep in mind that you have a fairly small layer height (0.12mm) in relation to the nozzle diameter. This increases the difficulty to get a good result.
Most use 0.2mm or 0.16mm layer height, and only go lower to improve surface quality on shallow surfaces.
Keep in mind that the hull line on a benchy is a challenge and requires manual changes to the gcode to get really rid of it.
I thought about this too, it’s recommended to go between 25% up to 80% of nozzle diameter so maybe I’m a bit too much on the edge of this lower limit, I will give a shot at 0.2mm layer height as it’s the most common default value.
Hi, so after experimenting with nozzles layer height etc and drying I can tell a few things :
Drying your filament for a good 10h at least indeed reduced the artifacts I’ve seen so for anyone with same artifacts consider a thorough drying it will certainly help improve this issue a bit.
As change in speed will in fact make a line look different I’ve found that reducing overall print speed will help to average all line speeds, reducing speed artifacts.
Calibrate the filament yourself, do the Flow Rate and then Flow Dynamics. BambuLab’s default settings will print well but after many tests you will certainly see better results with your own calibration. This was especially true for my 0.2 nozzle, default settings had under extrusion and also for my PLA-CF that had severe under extrusion.
In real prints many of the issues you can see on a Benchy will disappear or be heavily reduced.
PS : sorry I did not had time to respond sooner I was very busy recently. And thanks for everyone’s help.
