Ensure that you have some 📄backlash between the motor gear and the plastic gear.
- Gauge this with filament loaded and the spring tensioned (the backlash will reduce a bit once it is loaded).
- You want a little backlash, but not too much.
This is adjusted by moving the motor itself up and down.
The motor plate has 3 slotted screw holes to allow for adjustment:
- The top two screws are easily reachable.
- The bottom left screw can be reached by opening the filament latch fully and using a ball-end hex driver.
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📌Repeating patterns in extrusion
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Accelerated wear and damage of the plastic gear, further contributing to repeating patterns in extrusion.
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This can cause permanent extrusion consistency issues until replacement. Check the spaces between the gear teeth. This gear is damaged:
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📌Repeating patterns in extrusion
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Clacking noises during retraction and pressure advance moves
- Adjusting backlash can help considerably with these issues, but is not always guaranteed to fix it.
- These issues can also be caused by poor quality BMG parts. Genuine Bondtech or Trianglelab BMG parts are best.
- Galileo/Orbiter seem to be less likely to have these extrusion patterns in my experience. Bowden systems are also less prone.
- Test prints: 📄https://mihaidesigns.com/pages/inconsistent-extrusion-test
- Examples:
- See 📄"Setting Expectations"
- The left cube shows an "innie-outie" pattern across each extrusion line.
The right cube is with properly adjusted backlash, and the pattern is lessened. - "Wood Grain":
- Diagonal patterns:
Note: this kind of pattern can also be caused by mechanical issues with printer axes.
I don't have a Mini Afterburner so I can't give an exact process for tweaking it. I believe it also has some slotted screw holes to allow for adjustment.
I have heard that loosening and threadlocking these screws may also help with its extrusion consistency:
