2
$\begingroup$

I'm currently facing a Z banding issue that frustrates me more and more.

My printer is a modified Anycubic I3 Mega.

Customizations:

  • Mainboard: Bigtreetech SKR 1.4 Turbo
  • Stepper Drivers: TMC 2208 v3
  • Hotend: E3D Titan Aero
  • Hotbed: 5 mm aluminum base plate with a 200 W 12 V silicon heat mat and 3 mm hard paper as print base
  • External MOSFETs for the hotbed and hotend each
  • Bigtreetech 3.5 inch TFT screen as display
  • BL Touch sensor
  • Marlin version 2.0.6.1

What I tried to fix this issue:

  • check leadscrews for debris
  • cleaned leadscrews and applied new grease
  • checked Z couplers and hand tightened all screws
  • checked tightness of the Y/X axis belts
  • increased the driver current
  • replaced the 12 V 25 A PSU with a 12 V 30 A PSU
  • Extruder steps re-calibration
  • PID auto tune for hotend and bed

Pictures of the XYZ calibration cubes I printed:

enter image description here

enter image description here

Used slicer parameters (Prusa Slicer):

  • material: PETG
  • 240 °C / 100 °C hotend/bed
  • Infill 30 % with 60 mm/s
  • outer perimeter with 30 mm/s
  • 100 mm/s travel speed
  • 1 mm retraction with 40 mm/s retraction speed

The number of these horizontal lines and their occurrence is different on each print.

Any ideas?

Improve this question
$\endgroup$
5
  • $\begingroup$ Hi welcome to 3DPrinting.SE. It looks like your Z crew sometimes misses some steps. Did you measure the height of the calibration cubes. $\endgroup$
    – 0scar ♦
    Commented Feb 16, 2021 at 13:46
  • $\begingroup$ @0scar My calipers are not that exact but yes, it looks like its a litte bit too small. On my latest print I have 4 of those rings and it measures 19.4mm. During print it looks a lot like the z is not moving up for one layer resulting in printing the next layer on the same hight resulting in squishing the old layer which creates these rings. $\endgroup$
    – zero695
    Commented Feb 16, 2021 at 13:55
  • $\begingroup$ @0scar so what could possibly cause these missing steps? $\endgroup$
    – zero695
    Commented Feb 16, 2021 at 14:53
  • $\begingroup$ Are you sure the stepper drivers for the Z are correctly configured, enough current? $\endgroup$
    – 0scar ♦
    Commented Feb 16, 2021 at 14:59
  • $\begingroup$ Yes I am. The current ist set to X 860mA Y 860mA Z1 950mA Z2 950mA E 850mA. M122 shows no errors or anything suspicious. $\endgroup$
    – zero695
    Commented Feb 16, 2021 at 19:03

1 Answer 1

Reset to default
1
$\begingroup$

So it looks like I finally resolved that issue. I compiled a complete new firmware based on the Marlin bugfix branch. Before I was working on the sources provided in the Bigtreetech GitHub. I started from scratch and put all the settings I needed into the Configuration.h and Configuration_adv.h. Now all rings are gone. Either there was really a bug or something or I messed up something in the firmware I used before and beginning from scratch solved it.

Improve this answer
$\endgroup$
3

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .