Hello I'm new to 3D printing and I noticed some problem with my print.

I've print it 3 times and relevel the bed now, I found that the right lower corner always have holes, enter image description here some string problem enter image description here lastly, place where there should be a full line suddenly become string like, and it always happen at the same place enter image description here enter image description here

It's like my extruder pulls out the filament or fails to create filament in area that should be filled with filament, is it normal or did I set my printer wrong? I'm afraid it might cause holes in my new print.

there's also some stringing problem that cause the layer to be uneven.

Slicer: Cura 4.6


enter image description here enter image description here enter image description here enter image description here

my printer is anycubic 4 max pro

  • $\begingroup$ Please share what slicer you're using and relevant settings, especially speed, retraction, and temperature. Since you mention stringing, that's likely the root cause of the underextrusion in the corner there - any stringing is material lost in one place that then doesn't get deposited in the place it was supposed to go, and it's usually caused by wrong retraction settings (wrong = off or too low, in most cases). $\endgroup$ May 16 '20 at 7:07
  • $\begingroup$ Hi, welcome to 3DPrinting.SE! Note that you problem is very similar to "What causes ripples on part of first layer?" with an answer describing what may have caused this. Note that the corner without filament is also caused by this issue. To cut it short, your nozzle is probably too close to the bed. $\endgroup$
    – 0scar
    May 16 '20 at 8:42
  • $\begingroup$ Possible duplicate of "What causes ripples on part of first layer?"? $\endgroup$
    – 0scar
    May 16 '20 at 8:43
  • $\begingroup$ @0scar I've updated my question, it always string in the same place like the picture, are those also affected by nozzle height? $\endgroup$ May 17 '20 at 3:00
  • $\begingroup$ Looks like the retraction settings are not optimal also. $\endgroup$
    – 0scar
    May 17 '20 at 6:39

From the wispy horizontal lines within the perimeters in your second image, it appears that the nozzle is still oozing material during the travel moves. This is likely causing the hole in the corner and the wispy perimeters too. When the extruder reinserts the filament into the hotend after a travel move, it expects the same amount of material to be in the nozzle as when it extracted the filament, but some material has oozed out during the travel move so that is not the case. I had a similar issue with my printer, and was able to mitigate the problem by increasing the retraction extra prime amount in the material section of Cura. This should compensate for the material loss during the travel move by reinserting the filament slightly farther when starting the extrusion. This solution is not perfect as different lengths of travel allow different volumes of filament to ooze from the nozzle. If you want perfect prints, you may have to tune this to the model you are printing: larger models usually require larger travel moves which would allow more time for plastic to ooze from the nozzle.

If you try this, make sure to look for blobs at the start of extrude moves. If the prime amount is set to high, it can create blobs on the side of the model (or inside depending on which perimeter is extruded first) which could cause tolerance issues on more complex parts.

Personally, I have also added a small coast distance to the end of each extrusion (located in Cura's experimental section). This allows the nozzle to ooze into the perimeter of the part which should decrease the stringing on travel moves, and thus loss of material on travel moves.

  • 1
    $\begingroup$ This is all hacks to try to work around a problem that's entirely eliminated by correct use of retraction. $\endgroup$ May 24 '20 at 23:08
  • $\begingroup$ @R..GitHubSTOPHELPINGICE ... and temperature and travel speed ;-) But indeed true! $\endgroup$
    – 0scar
    May 25 '20 at 7:15
  • $\begingroup$ @0scar: In my experience at least with non-exotic materials, as long as retraction is right, temperature and speed can be just about anything reasonable and still not cause oozing. It'd be interesting to run an experiment like this, along the lines of "print enough lines to get extrusion consistent, then retract and start traveling in circles and measure the time until any material is observed exiting the nozzle". $\endgroup$ May 25 '20 at 16:13

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.