#Inconsistent extrusion on seam lines

1 messages · Page 1 of 1 (latest)

turbid current
#

Hi everyone,

I'm trying to figure out what's causing inconsistent extrusion specifically at the seam line of my prints (usually visible on corners). It seems to always happen where the seam is located. Recently I had a partially clogged nozzle and replaced it (Unicorn 0.4 mm). After the swap, I experienced heavy stringing, so I recalibrated everything I could:

  • Temperature;
  • Flow Rate;
  • Pressure Advance;
  • Retraction Distance & Speed.

Stringing improved significantly, but I'm getting inconsistent extrusion at the seam.

Additional details:

  • Filament was dried;
  • I tested with different filaments (same result);
  • The issue appears mostly at corners where the seam is placed;
  • Sometimes it's very noticeable, sometimes barely visible.

The first two photos show prints right after the nozzle swap (before recalibration). The second and third photos are after all tuning.

Printer: Ender-3 V3 KE
Nozzle: Unicorn Nozzle 0.4 mm
Slicer: Creality Print V6.3.0.3420 (Linux)
Material: PLA+
Flow Ratio: 0.99
Pressure Advance: 0.06
Retraction Length: 0.5 mm
Retraction Speed: 30 mm/s
Wipe While Retracting: Yes
Fan Always On: Yes
Print Temperature: 210 °C
Seam Position: Aligned (Sometimes Back)

At this point I'm not sure what else to change. Could this still be a retraction issue? Or something related to pressure advance/seam settings?

Any suggestions would be greatly appreciated!

before1.jpeg before2.jpeg after1.jpeg after2.jpeg
naive furnace
naive furnace
#

"Seam gap" might also be something to investigate.

quasi whaleBOT
#
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turbid current
#

I tested three different PA settings: 0.051, 0.048, and 0.045 (photos are in this order). They all look pretty similar to me, but 0.045 seems slightly more consistent overall, especially on the cylinder seam, so I'm leaning toward keeping that value. What do you think?

One thing I did notice: all of the square test prints show a small seam interruption on the right side. It's consistent across all PA values, so I'm guessing it's unrelated to PA at this stage. Could this be related to acceleration speeds?

0p051.jpeg 0p048.jpeg 0p045.jpeg
naive furnace
# turbid current I tested three different PA settings: 0.051, 0.048, and 0.045 (photos are in thi...

I'm not sure they kinda of look the same from here..

i'm used to looking at this test... sorry!
https://ellis3dp.com/Print-Tuning-Guide/articles/pressure_linear_advance/pattern_method.html
the line test might be more accurate.
scarf seams might do better on round walls. (look up teaching techs vid on scarf seams)

flow + rapid speed change can interconnect.... but using dynamic layer hieght can also cause this effect too.. i wonder if it's a klipper smoothing thing?

Ellis’ Print Tuning Guide
Pattern Method

Ellis’ Print Tuning Guide

turbid current
#

Thanks for the suggestions!

I agree the cube/cylinder comparison isn't the most sensitive method. I've now run the Ellis pattern test to dial in PA more precisely (attached). I just changed the filament color so I could actually see something in the printer bed, hahaha. The best results for me are in the 0.04-0.05 range.

I'm not using dynamic layer height, so that shouldn't be affecting the results. I'm not entirely sure about the Klipper smoothing settings, though. I've attached my current speed and acceleration settings as well in case something there stands out.

I'm not very familiar with scarf seams, since the option is in beta mode on Creality Print, but I will certainly look into it, thank you!

pattern_method.jpeg speed1.png speed2.png
naive furnace
turbid current
#

I was originally running 0.06, which appears to have been responsible for the inconsistent gaps.

quasi whaleBOT
#
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naive furnace
quasi whaleBOT
#
This post has been closed due to inactivity.

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