12.4 Nozzle cleaning
Use a wire brush to clean the nozzle from outside. Heat the nozzle before you do so.
If filament is not extruded from a nozzle (or in very small volume), first check the extruder fan
is working properly and that the temperature is set correctly (PLA 210 °C; ABS 255 °C, HIPS
220 °C, PET 240 °C). Also check that the filament was correctly loaded into the extruder.
If the filament pours out at least a little, check the direction. If it swirls and goes up to the
hotend you need to clean the nozzle.
First you have to move the extruder to the rightmost position, out of the way of the heatbed,
to reach the nozzle from below.
Heat the nozzle according to filament you want to print from, load the filament and put a
bundled acupuncture needle
(0,3-0,35 mm) into the nozzle from below - between 1 and 2
cm deep.
Choose
Load filament
option from the LCD menu and check if filament is extruded properly.
Put the
acupuncture needle
into the nozzle again and repeat these steps a few times more.
When the filament is extruded properly, the nozzle is clear.
12.5 Replacing / changing the nozzle
Preheat the nozzle (LCD menu -> Settings -> Temperature -> Nozzle) and set the
temperature to at least 200°C. Heating the nozzle is crucial for removing the old nozzle and
putting in the new one.
1) Move the extruder body upwards to get to the nozzle end (LCD menu -> Settings ->
Move axis -> Move Z -> Set the height by rotating the LCD knob and then confirm).
2) Unscrew the screw on
fan
mouthpiece
and the two screws on the
print fan
and
remove both parts
(Pict. 35, part 1)
.
3) Remove the two front screws on the
nozzle fan (Pict. 35, part 2).
4) Unscrew the two screws holding the
extruder cover
(Pict. 35, part 3)
. Even though
the nozzle itself is accessible directly, we recommend to take the extruder cover to
get access to the heating element.
5) Now the whole nozzle body is accessible
(Pict. 35, part 4)
.
6) Hold the heating element with a spanner (size 17) and unscrew the nozzle
(Pict. 35,
part 5)
.
Be careful, the nozzle is still hot!
When the new nozzle is inserted, tighten it while the nozzle is preheated. While tightening do
not forget to hold the heating element with the spanner. Re-assemble the extruder, insert the
filament and you are ready to print.
Be careful, the nozzle is hot during this whole process and can cause burns!
Be careful around the hotend thermistor leads, you can break them easily.
Be careful and don’t apply force to the nozzle or heater block, you can bend
the heatbreak easily.
It is a good practice to run
6.3.9 First layer calibration
after changing the nozzle!
60
Summary of Contents for Original Prusa i3 MK2S 1.75mm
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Page 25: ...Pict 11 Probe response diagram Now you are done 25 ...
Page 61: ...Pict 35 Nozzle change 61 ...
