Prusa i3 MK3 - E Xtruder​ ​ D Rive​ ​ G Ear

Pict.   36   -   Fan   error
The nozzle cooling fan is made by Noctua. These premium fans are known for their superb
quietness and exceptional performance.
You can turn off the monitoring in LCD menu under Settings -> Check fans for example if
you replaced one of the fans with a replacement not supporting RPM sensing.
12.1.3  Extruder drive gear
The hobbed drive gear on the extruder motor shaft can have build-up of filament shavings in
the grooves and cause under-extrusion. A small brass brush is an ideal tool to clean the
grooves, but a regular toothpick will do the job as well. Check and clean from the access
window on both sides of the extruder assembly. Clean what you can, then rotate the gear
and repeat. Nothing needs to be disassembled. Clean when you see signs of missing plastic
in the objects, e.g. missing lines of extrusion.
12.1.4  Electronics
It is good practice to check and eventually reconnect the electrical connectors on the mini
RAMBo board. Do so after first 50 hours of printing and then every 150-200 hours.

12.1.5  PEI rejuvenation
PEI can lose its adhesive powers after a couple hundred hours. Wipe it thoroughly with
acetone when you see models getting loose to restore the adhesion.
12.2  Print surface preparation
Print surface preparation is described in 6.3.2 PEI print surface preparation chapter.
12.3  Filament sensor
The optical filament sensor detects the presence of filament and also it’s movement.
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