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Filament jam (MMU2S)

Filament jam (MMU2S)

Filament jam (MMU2S)
Relevant for:
Last updated 2 years ago
Filament jam (MMU2S)
 Difficulty
Moderate
 Steps
6
 Available languages
CSDEESFRITPL

Step 1 Filament jam

Filament jam
Filament jam
During filament loading or unloading the filament can get stuck (jammed). The printer will try several times to fix it by itself, but if those attempts fail, it will light up LED above the affected filament.
The LED will be flashing with RED light:
Slow flashing - fault during filament load (moving the filament in the printer)
Rapid flashing - fault during filament unload (moving the filament out from the printer)
Note: green LED lights up in case of successful filament load/unload.
As soon as the filament jam is detected, the printer waits for the user's action. The print is paused, no need to cancel it. Following steps will explain how to fix it and continue printing.

Step 2 Finding the jam location

Finding the jam location
Finding the jam location
Finding the jam location
Finding the jam location
Start with releasing the Festo fitting on the Selector. Note it might be tightened, use 8mm wrench or pliers to release it.
Move the orange PFTE tube slightly up
Move the filament out from the orange PTFE tube
It might happen you won't be able to remove the filament from the tube, proceed to the other end of the tube, release the Festo fitting on the extruder and if needed remove the filament sensor cover and open the extruder idler.
In case the filament get's stuck inside the MMU unit, use the left black button on the unit. To load or unload the filament. (If the printer is at loading stage the button works in loading mode, if the printer is at unloading stage, the button is in unloading mode).
If the "Left button" doesn't load the filament, it is possible the filament is only in the white PTFE tube (has fallen out from the MMU idler). Using your fingers, push the filament in.

Step 3 Moving the filament through MMU unit

Moving the filament through MMU unit
Moving the filament through MMU unit
Moving the filament through MMU unit
It might happen the pulley inside the MMU unit damaged (ground) the filament. To be sure the filament ok, let's do following.
Using your fingers pull at least 10 cm of the filament from the MMU unit. This will ensure, a new and undamaged filament is loaded from the spool.
The following step will show you, how to cut the filament. Always cut it close to the Selector and make sure all the grinds are on the cut part you are going to remove.

Step 4 Cutting and straightening the filament

Cutting and straightening the filament
Cutting and straightening the filament
Cutting and straightening the filament
While cutting the filament make sure it is close to the Selector and all the damaged parts of the filament are removed.
Check the tip of the filament, which was in the orange PTFE tube:
Any kind of string, sphere shape or other irregularity is causing the jam.
Take pliers and cut a sharp tip
While loading the filament to the MMU unit, its end (10-15 cm) should be as straight as possible:
Bent filament can be the cause of the jam.
Press the filament between your fingers and straighten it.

Step 5 Checking the filament

Checking the filament
Checking the filament
Checking the filament
Using fingers move the filament back in the MMU unit and leave about 1 cm sticking out.
Now, let's use the three black buttons.
The left button was already used if the filament was stuck inside the unit.
The middle button will be used now. Press it once and wait for the printer to finish the auto-check procedure.
If the procedure finishes correctly, the LED above affected filament will turn to red-green flashing, if the procedure fails it will remain red.

Step 6 Successful filament jam removal

Successful filament jam removal
Successful filament jam removal
Successful filament jam removal
Put back the orange PTFE tube, check both Festo fittings are tightened properly.
Press the right button and the printer will continue printing.
That's it!!! Consider yourself a 3D printing technician ;)

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