Unstable extrusion when a new perimeter starts after unretraction
This is only a cosmetic problem and does not really affect the quality of the parts.
There are no significant underextrusions or overextrusions which would affect the structural integrity of the parts. However, I would like to get a better surface finish for my decorative prints.
The problem:
The external perimeter line starting from the seam has a slightly higher/lower width, which makes a visually unpleasant line. This happens only if the perimeter line started from unretraction.
4 Replies
future-harlequinOP•2y ago
What has been calibrated:
Rxtruder's rotation distance, PA, EM, retractions, input shaper (visual methods).
Print parameters (white print above):
- PLA @ 220 C
- PA: ADVANCE=0.052, SMOOTH_TIME=0.01
- retract length 0.4, retract speed 40 mm/s, unretract speed 25 mm/s (I get same results in a wide range of retract/unretract speeds)
- z hop 0.2 mm
- wipe on retract off
- retract at layer change off
- speed external perimeter 120 mm/s, internal 160 mm/s, infill 200 mm/s
- accelerations 2500 - 5000 mm/s2 for printing moves, 7000 for travel moves
- external perimeters first off (seems to make a marginal improvement)
What affects the problem:
- retract at layer change on makes the seam looking more consistent but the perimeters are still visually unpleasant
- disabling retractions makes a massive improvement on the perimeters visual quality
- lower printing speed (staying below a reduced flow rate) makes marginal improvements
future-harlequinOP•2y ago
Prints with zero retraction (black). The seam and the perimeters are much better, the extrusion width is consistent. The photos are taken in harsh lighting but the real look is very good.
You missed a zero in your pa
future-harlequinOP•2y ago
Yes, it was a typo, thanks. The actual PA is 0.052.