Every once in a while the filament will jam in the print head, this can be caused by a few different things (like moisture in the filament), but is always a pain because you normally lose your print. We will give some suggestions for preventing the head from jamming and then walk through several ways to get the print head cleaned out and working again.

How to prevent a jam

  • Make sure you are storing your filament in a Ziploc bag with a desiccant inside to keep moisture from being absorbed into the filament.
  • Make sure you are using the proper temperature, extruding at too low a temperature doesn't extrude well but extruding at too high a temperature can cause problems too. 
  • Check to see that your spool is able to spin freely, if it gets caught on something your printer can stop extruding.
  • Make sure you have a good layer height. If your print head is too close to the bed it will try and force the filament out but is capped off by the bed.  This will create back pressure that will cause your printer to jam. 
  • If you experience jams frequently try and calibrate your extruder.
  • Measure the diameter of your filament with a pair of calipers several times and then
    take the average and enter it into the filament settings in MatterControl.
Recognizing a Jam
  • Your printer will stop extruding so you will start printing in mid air. 
  • You will hear a clicking noise as your extruder starts to slip
  • The filament doesn't lay down consistently and starts to web and blob

Filament tied in a knot
  • Sometimes the filament on your spool can get wrapped around itself and tie itself in a knot.  This also cause the printer to jam. If you notice this before the print gets ruined, try and untie the filament like you would a knot. If the print did get ruined abort the print by pushing the selector knob to bring up the menu, scroll down to "Abort," and press the knob to select it. After the print has stopped untie the knot in the filament and start your print over. 

Bends and kinks in filament
  • If the end of your filament is bent, kinked, or has other deformations it can cause friction inside of the Bowden tube walls.  If you have sections of filament that have these bends in them, break or cut them off and put the clean section of filament back into your printer and start the print. 

Fixing a jam caused by a clogged hot end
  • If you experience a jam, the first thing you will need to do is stop your printer
  • Press the knob on the screen to bring up the main menu and go to the second option down which should say "Abort."  Select it and your printer should stop as soon as it is done with its current move. 

  • Bump up the hot end temperature about 20 degrees.
  • Press the knob to bring up the main menu, scroll down to the "Prepare" menu, and press the knob to select it.

  • Scroll all the way to the bottom of the menu to the "Set Temperature" option.

  • Select the "Hotend" and use the knob to raise the temperature about 20 degrees above what you would normally print at and then press on the knob to exit back to the prepare menu.

  • Relieve the pressure on the filament.
  • You can press down on the lever on the extruder, and then pull back on the filament line a little bit until it comes loose from the hot end.

  • You can also retract the filament using the printer by going to the main menu and scrolling down to the "prepare" menu. Press the knob to enter the menu and then scroll down to the second to last option which is called "Extruder". After you select the "Extruder" scroll down to the "Retract 5mm" and select it several times to draw the filament out.

  • You may have to remove the bowden tube and manually pull the filament out of the hot end. To do this start by sliding the black plastic bowden clip sideways and then removing it from the hot end.
    Note: In order to remove the bowden tube, the hotend must be heated above 150˚C. 

  • Next remove the tube by pressing down with your fingernail on the black ring at the top of the hot end and then pull upwards on the Bowden tube until it comes out. The filament may or may not come out when the bowed tube, if it does not pull firmly on the filament until it comes free.

  • Extrude out your filament (by either pressing the lever on the extruder or going through the same routine as retracting but press "Extrude 5mm" instead) until you can see the end of it to make sure that you don't have a little blob on the end that can cause jams, if so break or cut that piece of filament off. 

  • Press a short section of filament that you have lying around to clear out the jam by pressing it into the open top of the hot end until the material comes out. 

  • Put the Bowden tube back into the hot end by firmly pressing the tube into the top of the hot end. Make sure the tube is seated all the way down into the hot end. 

  • Extrude the filament by either pressing on the lever on the extruder or by following the same steps as retracting with the menu but select "Extrude 5mm" instead of retract several times until the filament starts being pushed out of the nozzle. 

You should be jam-free and ready to go.