repeatable problems in same layers
Hi,
I'm new to printing and therefore unable to describe my problem using the correct terms. I don't know, if the issue was already mentioned here in the forum, but I couldn't find my problem.
Since I built my MINI+ a couple of days ago, I only did some test prints. Some went really fine, like the included treefrog or the PRUSA-plate. Others were experiencing serious troubles. For example: the gcode from https://www.prusaprinters.org/prints/62451-prusa-mini-z-axis-dust-cover/files . (printed as it is)
The base itself is printed good (imho), but when it comes to the four walls at the top, the layers go unregular und corrupt. The extruder is making strange noises then and no more filament is processed to the print. If I don't stop the print at this point, the extruder gear will destroy the loaded filament and it's spaces will be filled with the filament.
Maybe, a picture helps to understand the problem. And everybody likes pictures:
I made a couple of test using different materials (all PLA). Every time, the troubles start at nearly the same point.
(blue = Prusament, black = sample from the MINI+ kit, orange = basic filament by a global online shop, named like a river)
Does someone know the problem, maybe a solution? Or a link the the problem here in the forum?
Thank you.
RE: repeatable problems in same layers
I would check two things. First would be the tension on the extruder. The instructions say to have the head of the screw about flush with the outside wall of the extruder housing when no filament is loaded, if I remember correctly. During the part of the print where it is failing, the printer is retracting the filament and then trying to push it back out to start the next layer/section. If the extruder is too loose it won't be able to bite down on the filament enough to push/pull during retraction and will just grind through it. You also want to make sure the tension isn't too tight because that can also cause issues.
The other thing to check is the known clogging issue on the hotend. Some people are finding the PTFE tube in the heatbreak is slightly too short, causing a gap and allowing the filament to leak out of its guided path and cause some clogging. That one is fairly well documented on this forum and on reddit. Here are some links talking about it. I hope this helps!
RE: repeatable problems in same layers
@grevtech
“First would be the tension on the extruder.” Concur.
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Chuck H
3D Printer Review Blog
RE: repeatable problems in same layers [answered]
Thank you both for your answers. It helped me a lot, specifically knowing the correct words for the problem now. 🙂
Adjusting the tension indeed helped for one print, then it got worse than before. So I went for the replacement of the PTFE tube. This solution seems to last longer, even if I only did 4 prints yet.