Maybe try with bridges speed equal to walls speed ? It seems that lot of pressure is released when it slow down for bridging.
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Have not done that yet, but seems I‘m not the only one having these issues:
I did again increase temperature, this time to 280°C. Everything else was unchanged from Generic PETG. Result is way better now, artefacts are almost invisible now.
I will post some images, but I would like to do some more investigation regarding temperature.
How can I create a print where temperature is increased by 5°C every 20 layers? Then I would like to print a whole for every temperature, starting at lets say 230°C and continue up to 300°C.
Already when I printed with my ultimaker + and PLA I always increased printing temperature way above the recommended value. I printed PLA @ 235°C which was quite the max the ultimaker would allow. I was very happy with the results I got.
Seems I should have sticked to the principle “recommended temp+30°C” earlier^^
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How about using a temperature tower, such as: https://www.printables.com/model/355077-parameteric-temperature-tower.
Well, if that’s not exactly what you want, you can adapt it to something you do want.
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FWIW, I print Sunlu Grey PETG almost daily without issue using the default Generic PETG profile at .16 and .20. I’ve only used Grey if that matters. Only time I had any issues I noticed the humidity was like 27% in the AMS so I dried if in the Sunlu dryer and changed out the silica packets. It went back down to 21-22% and everything was fine again.
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I have to try. I just want to make sure that a similar feature (a whole) is included in the tower which causes the artefacts.
I don‘t know what is different, but drying did not help at all in my case. I will save this energy for something useful!
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What’s the conclusion? They’re all labeled 12. The one on the left looks terrible, but the one on the right not as bad.
If raising the apparent temperature to 280C seems to help, then wouldn’t that tend to imply that either the temperature sensor is either faulty or has some kind of loose connection?
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280°C sounds high for PETG, I am a bit concerned by the heat block of this printer, doing test with PLA & High flow Nozzle (CHT) it rapidly cant handle more than 220°C when increasing print speed, using standard nozzle it seems that when printing fast even with high temperature setting the plastic is not melting as it should be. My opinion is that if the flow is not very low the heat cartrige and the nozzle just does not heat/melt the plastic as they should.
This wil explain why you have to set such a high temperature to get a sufficient heat to melt PETG correctly.
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But it wouldn’t explain why many (most?) of us don’t have to set such a high temperature to get good prints with PETG. It seems there’s something different/defective about T_guttata’s machine that’s causing the faulty PETG prints that he’s getting.
The one thing we could try that we haven’t yet is to have someone like @skyme send T_guttata a slice file of the test object and have @T_guttata print from that. Or visa-versa. Probably overkill, but if it then still prints differently at least it would tend to rule out any possible misconfiguration in T_guttata’s slicer and basically prove to Bambulab that Bambulab needs to fix T_guttata’s X1C while it’s still within the warranty window.
Unfortunately it is not the temperature alone. While it certainly helps (the cube turned out much better), I reprinted the object from post 75 and it looks as before.
Regarding the images: keep i mind that I did most images with a microscope, which makes things visible, which you won‘t even notice otherwise.
I did not get any answer from bambulab yet.
Next I will print different objects in various orientation on the build plate to see if there is any effect on the print quality. The link I posted shows that I‘m not the only one with these issues
I got an answer from bambulab. I shall clean the rods and check belt tension. I did that, without success.
But I got a new finding.
I printed a slightly smaller piece in 5 orientations on the build plate. Turns out that the orientation does not really matter but every piece has one side which is far better. Therefore, printing direction must have an influence?
Here are a few images (standard profile but 280°C):
better side:
bad side:
Since one side is far better than the other side, print direction must matter. I therefore don’t think the issue can be caused by heat transfer issues of the nozzle.
I only see 2 possible causes: software bug or an issue with belt tension / resistance.
If it were a software bug, wouldn’t it be affecting everyone?
As for belt tensioning, how is one supposed to measure it? I know that for treadmills there’s a phone app that can determine how tight the belt is by using the microphone to listen to the vibration frequency when you pluck it. For 3D printers, though… is there some kind of equivalent tool to take the subjectivity out of it?
Just a wild ass guess, but perhaps there’s a faulty bearing that might explain the directionality of the fault.
I feel sorry for you. One of the major benefits for this type of machine is that you shouldn’t have to dive into the weeds to figure things out on your own. It should “just work”. That’s part of what you paid for, but you got hassled instead. I’m very interested in how this plays out with Bambulab and whether or not you get adequate support from them.
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You may have already answered this or performed it but have you tried changing the nozzle?
How does your infill look? Try printing one without any top layers.
I found that the default “reduce infill retractions”, plus the default grid infill pattern, plus oozing PETG made an absolute mess out of inside of the model. That can have knock-on affects that could affect surface quality.
@T_guttata Sorry if I missed some information because I did not read each and every post, but I still want to distinguish the cause between software and printer.
So again, have you tried to print any gcode that gave a good result on another printer, or vice versa, has anyone printed gcode generated by your slicer?
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I’m glad to help out - just drop me a line. We all learn more about our machines by troubleshooting such errors!
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Regarding SW you might be right or not. SW bugs can sometimes be very wired. The ones which occur always will be recognized by Bambulab. But there might be special situations which they do not recognize.
@ Jrock
I did not change the nozzle yet. Now that I have almost tried everything else, I should probably do that.
@ 3dball
I printed the file from hant.szabi, this was the image with settings “9”.
Ok, nevermind.
If you have also already tried a different (proven good) filament brand I’m running out of ideas.
Did I understand it correctly that if you rotate the artifacted face by 90 degrees that the artifact on that face goes away? Is it the X axis or or is it the Y-axis that’s implicated?
