X1C, 4mm nozzle, 3 loops, random and painted seams. PPA-CF has been dried a few times in Sunlu E2 at 110C. Stored in the E2 with plenty of dessicant and I’m printing right out of the E2. Manual calibrations done.
I’m trying to dial in my PPA-CF printing. On the flow calibration test, the part with the numbers came out fairly poorly at any flow rate. As you can see in the picture, when I print objects, there are often strings hanging out of the bottom of the print (see the inside diameter on the right, its a little dark.) The lumpiness on the top in the picture isn’t present after the final layer is printed, but it doesn’t seem good.
I tried increasing the retraction length to 1mm, and added .4 Z-Hop when retract, but it did not make any difference.
I don’t know how to make the filament any drier than it is right now. I’ve baked it a few times and store it with desiccant. I’ve printed with the dryer running too.
Any ideas? Am I on the right track with the retraction and Z hop and just need to keep trying, or are there some other settings you think might help?
Although I have not printed PPA-CF, I have had quite good success with enabling “wipe on retract” for most filaments. That can help a lot with oozing & stringing. Z-hop unfortunately did not help me nearly as much.
Regarding the lumbs, there may a number of root causes such nozzle temp too low, too much cooling, too fast, too low an infill,…
Personally, when running into issues, I first rule out filament moisture (which you have done) and slow down the print. The latter also helps to better observe the failures as they are occuring.
You dried the filament with rigor, that’s a lot more than most people do as part of diagnostics so hats off to you.
I’m leaning towards flow issues possible caused by temperature (most likely) or speed (less likely).
Their are three things you hadn’t mentioned so just in case you haven’t tried this rout here goes:
Print a true temp tower, by that I mean it must either be one generated by the slicer - I don’t know if Bambu Lab ever stole that from the calibration menu from Orca since I’ve not used Bambu Studio since 1.6 and have been on Orca ever since. Once you slice the tower, go to temp on the menu and make sure it shows different temps on display at each layer. If it’s one color then all though is a static model with no color variation. Here is what that menu looks like in Orca, you would have to select customer and then enter the range for PPA-CF.
In case you don’t have Orca, here’s a saved test tower using the X1C definitions. Note: I don’t have an X1 so I could not test this:
◊ PPA-CF Nozzle temperature test.3mf (293.6 KB)
Check the top and side walls. Try increasing both, 3 may not be enough, you may have to increase to 4-6 and also, remember to change the default wall order to outer inner.
And last, did you try slowing the printer down like putting it in quiet mode? That might be a quick test to try out. If it improves the result, that confirms flow issues.
If you succeed, let us know what worked so that the remainder of the community can benefit. I haven’t played with PPA-CF because my P1P just can’t reach the temps. I have a new non-Bambu machine that might be able to do it but haven’t had a chance to try it so I am very intersted in what succeeds.
I was interested in some of the calibration tests Orca offered so (with great difficulty) I got it running. I went down the menu running tests through the retraction test and stopped after that. The results either pointed to the default value from Bambu being the right choice, or the results didn’t really give me any actionable information. I was enthusiastic about the temperature tower, but it didn’t ultimately give me any data. There was some of the stringing I saw on my actual prints at 285C, but the actual parts were all printed at 300C where there was no stringing on the temperature tower.
I’m going to print some smaller example parts to see if I can replicate the issue and then try tweaking settings from there.
Slowing the print down seems promising so I will definitely try that as one of my tests.
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