Troubleshooting a “clicking extruder”:
The first thing you may notice is the sound your extruder is making, hence why we call this the "clicking extruder". This is when the extruder Motor is not able to push filament through the nozzle resulting poor print quality. Because of the range of potential causes, diagnosing can be a bit challenging, but not impossible. Luckily we have a comprehensive list of common causes with some pretty simple fixes that you can try at home.
There is the list below but if you'd like some expert help, please contact us with some details and we'll be happy to reach out with suggestions.
Most of the mechanical reasons directly affect the thermal dynamics of the extruder. There is a careful balance of heat and cooling that must happen in order for your machine to print successfully & if anything changes it can quickly limit the printers ability to print.
Heat Sink Compound
No heat-sink thermal paste around the needle. In the channel where the needle sits inside the clamps there should be some white or grey thermal paste around the needle (as exhibited in the picture below). Wait until your extruder is completely cooled, then open the front clamp using the 3.0 mm hex key. Inspect the channel and if there is none, add a smear of paste enough to fully coat the needle between the circlip and heat block. Once finished return to it's position and tighten the clamp down.￼
The rear fan is having difficulty spinning. Sometimes dust or PLA bits build up in the 40 mm fan that blows on the rear clamp. This can cause blockage of the mechanism that allows it to spin. The fan is programmed to automatically turn on when the extruder is heated to 50 degrees Celsius or above. Sometimes PLA gets stuck in there. Try giving it a gentle push start with your finger, if it begins to spin, this may be a sign that you need to clean it (I recommend) a can of compressed air.
Another option, if for any reason the compressed air doesn’t remove the debris, is to clear it manually. Before trying this it is important to wait for the extruder to cool completely. Using the 2.5 mm hex key loosen the two rear bolts and remove debris manually (I’ve broken many a fan blade trying this while it’s running, definitely wait until the block is completely cooled and the fan is off).
Clamps are loose. If the needle seems to be wiggling in the clamps it’s possible the front bolt needs tightening. There should no play in the extruder when it’s clamped properly. If the clamps seem tight and there is still play it could be a loose set screw in the heater block.
Loosened set screw
The set screw has loosened over time and the heater block has migrated along the needle. If you notice that the length of the exposed tip of the needle is greater than 3 mm there is a possibility that the heater block needs to be readjusted. Since PLA can lock the block in place, the easiest way to do this, is while the extruder is hot. Using a 2.0 mm hex key loosen the setscrew in the right hole of the heater block. Using either a driver or crescent wrench pliers gently wiggle the block down the needle, careful not to pinch the cables. The base of the block should be resting just above the section of the needle where it transitions from tapered to straight. Once properly adjusted, re-tighten the setscrew so that it doesn’t migrate while printing. PLEASE USE EXTREME CAUTION WHILE THE EXTRUDER IS HOT.
Sometimes the combination of factors will cause heat creep within the clamps, such as printing at higher than normal temperatures, using a heated bed at higher temps, ambient temps over 80 degrees Fahrenheit, in addition to the above mentioned issues. You may just need to let the machine fully cool before trying your print again.
If the pinchwheel is not aligned just so along the motor shaft there will be friction that will prevent the filament from being pushed through. Loosen the set screw enough to allow play along the shaft. You'll need a piece of filament. Push the filament through the guide (if you have one) or the pinchwheel and lever arm (if you don’t) and into the channel in the clamps. You may observe that once the set screw is loosened that it will block full rotation. Full rotation is not required for this correction. You need just enough play to make sure the filament can easily enter into the clamps. Once done, tighten the set screw. Fully remove and push the filament through to make sure that there is smooth action into the clamps.
Debris in filament. Occasionally there will be a batch of filament that may have foreign matter in it. Luckily the design and shape of the nozzle will expel most debris, but occasionally there are larger bits that cannot be expelled normally. When this happens you will need to clean out the nozzle. We cover how to do that in this article here.
Retraction settings in your slicing software. If there's too much retraction, the needle will clog, you can try reducing the retraction and slowing down the retraction speed little by little to see if this helps. You can also test the gcode in this article and submit a Support Request with an image of the results.