Rotation_Distance Calc. and Extruder Motors w/ Odd Hobs

General Discussion
1

Basic Information:

Printer Model: Monoprice Maker Select Plus
MCU / Printerboard: AR100 / Recore
klippy.log (1.3 MB)

Describe your issue:

I am trying to understand these ideas:

  1. The printer is pushing too much filament.
  2. The hob has an “irregular” amount of teeth.
  3. My rotation_distance on the extruder has been attempted many times due to hob teeth and filament extrusion from the lessons which can be found here: Rotation distance - Klipper documentation (klipper3d.org)

I tried the gear ratio and the diameter * 3.14 which does equal 18.84.

If need be, I can try to account for each tooth on the hob.

Seth

P.S. If you have any words of wisdom, please let me know. Also, there was clicking like the filament was being forced too quickly before it could melt…

Is this normal w/ PLA and quick movement from the mechanics?

2

Some remarks:

  • An “irregular” amount of teeth will significantly impact your print quality. Recent findings have shown that an absolute regular and round gearing is crucial. Any run-off, misalignment, lack of concentricity or wobbling needs to be avoided
  • Follow the rotation distance tuning with a length of 300 mm or more: This will even out any errors but does not fix the points above
  • Clicking usually means that your extruder stepper is loosing steps. Nothing you want to have: Either too low torque of the motor, too low run current or defect / binding / crappy extruder
5 Likes
3

Thank you for the remarks.

I will probably have to accept it and get a new hob w/ a normal amount of teeth.

Seth

Update

The hob is contorted in a manner which makes it inevitable for the filament to slip into heat creep. updates…hopefully on the way one day. This printer is better than it seems!