I noticed my prints have gaps in the walls:
I found another question with some tips, but I tried everything suggested in there and, while it helped somehow, it didn't solve the issue; also, it seems the issue is present on many walls, but not all (or not at the same degree):
In the red circle is very pronounced, in the green one is almost absent, and in others (in another print), they were almost invisible if not absent.
My current print settings (all other flows are at 100%; see below the images for the textual version):
Quality
Layer height 0.12 mm
Initial Layer height 0.2 mm
Line width 0.45 mm
Wall Line width 0.45 mm
Outer Line width 0.45 mm
Inner wall(s) Line width 0.45 mm
Top/bottom Line width 0.45 mm
Infill Line width 0.45 mm
Skirt/Brim Line width 0.45 mm
Initial layer Line width 100%
Walls
Wall thickness 1 mm
Wall line count 2
Outer wall wipe distance 0 mm
Outer wall inset 0 mm
Optimize wall printing order ✓
Wall ordering Inside to outside
Alternate extra wall ×
Print thin walls ✓
Horizontal expansion 0 mm
Initial layer Horizontal expansion 0 mm
Hole Horizontal expansion 0 mm
Infill
Infill density 20%
Infill line distance 2.25 mm
Infill pattern gyroid [but really, the issue seems to be present with any infill at any density, at least up to 20%]
Connect Infill lines ✓
Randomize infill start ×
Infill line multiplier 1
Infill overlap percentage 10%
Infill overlap 0.045 mm
Infill wipe distance 0.1 mm
Infill layer thickness 0.12 mm
Gradual Infill steps 0
Infill before walls ✓
Material
Printing temperature 205 °C
Printing temperature initial layer 205 °C
Initial Printing temperature 195 °C
Final Printing temperature 190 °C
Built plate temperature 60 °C
Built plate temperature initial layer 60 °C
Scaling factor shrinkage compensation 100%
Horizontal Scaling factor shrinkage compensation 100%
Vertical Scaling factor shrinkage compensation 100%
Flow 100%
[All the flows at 100% besides Inner wall(s) flow, which is at 120%]
Speed
Print speed 50 mm/s
Infill speed 81 mm/s
Wall speed 25 mm/s [this is greyed out]
Outer Wall speed 34 mm/s
Inner Wall speed 67 mm/s
Top surface outer Wall speed 34 mm/s
Top surface inner Wall speed 67 mm/s
Top/Bottom speed 25 mm/s
Travel speed 120 mm/s
Initial layer speed 25 mm/s
Initial layer print speed 25 mm/s
Initial travel speed 60 mm/s
Travel
Enable retraction ✓
Retract at layer change ✓
Retraction distance 10 mm
Retraction speed 60 mm/s [with yellow background]
Retraction retract speed 60 mm/s [with yellow background]
Retraction prime speed 60 mm/s [with yellow background]
Retraction extra prime amount 0 mm³
Retraction minimum travel 1.5 mm
Maximum retraction count 100
Minimum extrusion distance window 10 mm
Combing mode All
Retract before outer wall ×
Avoid print parts when traveling ✓
Cooling
Enable print cooling ✓
Fan speed 100%
Regular Fan speed 100%
Maximum Fan speed 100%
Regular/maximum Fan speed threshold 10%
Initial Fan speed 0%
Regular Fan speed at height 0.2 mm
Regular Fan speed at layer 2
Minimum layer time 3 s
Minimum speed 10 mm/s
Lift head ×
Cooling during extruder switch Unchanged
