Nothing is coming out of the extruder

Nothing is coming out of the extruder

You are excited to start your first print. Everything is all set: the design is already finalised and the filament is already loaded, but nothing is coming out of your extruder! Here are questions to ask yourself why you are experiencing this problem.

  • Do you have enough filament?
  • Is the filament not feeding properly?
  • Did your filament snap?
  • Is the extruder grinding your filament?
  • Is your nozzle blocked?
  • Is your nozzle too close to the bed?
  • Does the print head miss the bed?

Do you have enough filament? 

You may think that this is a stupid question, but you’ll be surprised at how many 3D printing enthusiasts commit this gaffe from time to time. It is hard to see the filament reel in some 3D printers, hence why some wouldn’t notice that they’ve run out of filament.

 

Solution: It is easy to remedy. Just load up a new filament reel into your extruder. 

 

Is the filament not feeding properly?

 

You feed the filament into the mouth of the  extruder but it won’t push through. Or it could be that it can only push past partially but suddenly got stuck halfway through. Either way, you have a problem on your hands and forcing the feed of filament to push through can ruin your print. 

 

Solutions: It could be caused by a confluence of factors, including issues with the extruder motor or bowden tube, loose motor cable or, extruder blocker. 

 

  • Check if your extruder motor is clicking: 
    • If your extruder motor is emitting clicking sounds, the first thing you should do is look if your filament is deformed. If it has been flattened to become wider than it usually is, reduce the idler pressure on the feeder gear. On the other hand, you should increase the idler pressure if the filament has a gouge taken out of it.
    • Second, decrease the strain by reducing the amount of retractions or make the retracts less aggressive.
    • Third, inspect the PTFE liner and make sure that it is not worn out or degraded by turning up the heat too high at 260°C. It could also lead to clogs and leaks if it has been frayed or cut. This will cause the liner’s diameter to become smaller.
    • Fourth, the nozzle could be clogged. You can use our comprehensive guide to unclogging 3D printer extruder nozzle here
  • Inspect the Bowden tube: If your printer uses a Bowden extruder, check for the following: 
    • Debris inside the tube
    • Worn out areas with increased friction on the inside 
    • Too high bend radius
    • Frayed or cut tube
    • Pushed into the hotend
  • Probe into the feeder part of the extruder:
    • It could be that the filament has been eaten away by the feeder gear. Clean this section.
    • You should also adjust the idler pressure spring as it could be that the idler is not applying sufficient pressure to push the filament out. 
    • When the teeth of the feeder gear are worn, it could also cut your continuous flow of filament. These teeth should also be cleaned from time to time as they accrue debris. 
    • Ensure that the thermister is working as it may turn off sometimes due to the firmware settings. 
  • Check out if motor is working okay: If anything goes wrong with the motor (loose or broken cable, failed motor, loose connector pin, etc.), stop the printing immediately and turn your machine off. 

Did your filament snap?

You check your filament reel and there’s still plenty of material. Yet nothing is still coming out of the extruder. It could be that your filament snapped, an issue that is more prevalent in Bowden feed printers since the filament is concealed. Old and cheap filaments tend to snap easily, so you better make sure that your filaments are stored appropriately. A too-tight idler tensioner can also put pressure on the filament and cause it to snap. 

Solution: Just remove the filament from the printer as you normally do. If there is remaining filament inside the tube, you would need to separate the tube from the hotend and extruder. You can then heat the nozzle to pull out the filament. 

As for the idler tensioner, you can loosen it and only start adjusting the tightness when you start to print. 

 

Is the extruder grinding your filament?

 

There are times that the filament is skinned due to a clog, incorrect hot end temperature or a loose idler tensioner. It can result in no filament extruding from the printer. 

 

Solution: There are several ways you can fix this problem.

  • Tweak the idler tension’s settings: Loosen up the idler tension and load the filament. Tighten the idler until the filament stops slipping. 

  • Remove the filament: Remove the filament and cut off the area that is marked with signs of slipping. Help feed the filament into the printer by applying a gentle pressure to get it through the system. 

  • Make sure you have the right hotend temperature: It could be that you have the wrong temperature if the problem arises just after inserting a new filament.

Is your nozzle blocked? 

Everything seems to be going well with your printer, but it just won’t extrude the filament. It could be that your nozzle is clogged. There are plenty of reasons that this could happen: either an old piece of filament got stuck between switching 3D printing filaments or there is a buildup of carbonized filaments. 

 

Solution: There are plenty of ways to fix this, depending on the level and cause of clogging.

  • Poke around with a needle or a guitar string: Sometimes all it takes is inserting a needle or guitar string into the nozzle to remove the clogging when it isn’t that bad. After heating the hot end, pick up your tool of choice with a pair of pliers and insert it into the nozzle. Just move it back and forth carefully until the blockage is dislodged.
    • Soak in a solvent: For clogs caused by soluble filaments such as ABS, you can submerge the nozzle in the appropriate solvent to melt the blockage. You only have to remove the nozzle from the 3D printer and soak it in the solvent for 24 hours. Shake it every couple of hours. After the 24-hour period has passed, get a needle or guitar string to poke out the clog. If it still can’t be removed, soak the nozzle in the solvent for another 24 hours. 
      • Cold pulling: Cold pulling is the best method when the clog is due to carbonized filament buildup or transitioning from high to low temperature while printing. It is the hardest method and causes the most pressure on the 3D printer out of the three so only do it when all else fails.

        Cold pulling works by pulling a cool-enough yet still stretchy filament away from the sides of the barrel. 
          • Start by preheating the nozzle to remove the filament. 
          • You can do this by pulling out the bowden tube from the print head by removing the clamp that holds it. 
          • Heat up the hotend to around 230-240 C. 
          • Get 8 inches of filament and straighten it out to make it easier to insert.
          • Lower the temperature to 145C for higher temperature materials and 110C and 90C for ABS and PLA, respectively to cool down the hotend. While it is cooling down, continue pushing the filament down as far as it can go.
          • Once the print head is cool, pull the filament up in one quick and clean motion.
          • Keep repeating the process until the tip of the filament is clean.

     

    Is your nozzle too close to the bed? 

     If your nozzle is practically kissing the bed, then it would have no room for the melted filament to extrude. A too-close nozzle can cause your print to skip the first layers or even a blockage due to the backed up melted filament in the hot end. 

     

    Solution: You can configure either the height of the z-axis (easier) or print bed (harder). The latter is more difficult as you would have to level the bed and re-calibrate everything. 

     

    Does the print head miss the bed?

     

    This problem is unmistakable as the noise it makes will alert you immediately. This is caused usually by incorrect printer configuration, wrong printer settings in the software, or worn out or broken end stops.

     

    Solution: You can try to solve this problem with these 3 fixes.

    •  Observe the end stops: Check if the print head moves past the limits of either the X or Y position. If it does so and the end stop isn’t disconnected, it’s time to replace the end stops with new ones.
    • Set the correct printer in your printing software: If you selected a different printer from the one you’re using, the settings could be all wrong, therefore messing up the printing dimensions.
    • Check if there’s a firmware update: This comes in handy especially if your printer is newly purchased. After updating, go through the setup process and review your settings. 

     

    3d printing