In Part 1 of Unclogging Jammed Extruders, I covered removing the clogged filament by heating the extruder. Now, let’s review how to remove the assembly to check for a clog.
Disassembling the Extruding Assembly
If the previous procedure has not removed your jam then you likely have filament jammed in your extruder motor assembly. Removing this is not very difficult. Just remove the extruders from the carriage by removing the two screws you put in when assembling the carriage (see Figure 4)
Next, remove the fan of the jammed extruder by removing the two screws at the bottom of the fan. There will be 2 nylon spacer behind the fan on each of the 2 screws. Now you can remove pull the fan away from the assemble as well as the heat sink.
Now, to remove the motor you need to dislodge the plug on the top of the motor and loosen the motor mount screw. To release the plug you can use a small screw driver and pry each side of the plug upwards (see Figure 5). Next, loosen the top mount screw…there are two hex screws on the top of the extruder loosen the one in the most forward position. Do not loosen the wiring harness screw (see Figure 6).
Once these steps have been done you will likely need to cut your filament. Leave a small amount sticking out the top of the assembly so you can pull on it. Now your motor should be loose, but it’s unlikely that you will be able to remove it because the filament is still running down the length of the assembly. Next take your small knife or Xacto hobby knife and cut the filament at the top of the extruder barrel, just below the feed assembly (see Figure 7). To do this, look at the assembly from the front. There will be a very small gap between the barrel and the feed assembly. Use your knife to cut through the filament. You will not be able to cut it with one try, it will take many small cuts to cut through the filament.
Once you have the filament cut you will likely be able to remove the filament from the assembly by pulling it from the top of the assembly. If the filament will not pull from the assembly, it is likely caught in the extruder motor and/or roller. However, you should be able to wiggle the motor free and slide it rearward. Once you have the motor free you can move it to your workbench and free any filament that is jammed in the assembly.
Now, look down at the barrel from above and see if there is any filament in it. If so, try to remove the filament with a pair of needle nose pliers. If you are unable to pull the filament free, you may need to heat the extruder and retry removing it with the needle nose pliers. If you are still having difficulties removing the filament you may try and heat the extruder and then physically push the filament through the barrel and out of the extruder using a small diameter wire.
Once the barrel is clear you will reassemble the extruder in exactly the opposite order. Begin by sliding the motor back into the mount. Once this is done you must align the assembly exit hole and the barrel. The easiest way I have found to do this is to insert filament into the extruder and push it down through the assembly by pressing the thumb release on the assembly (see Figure 8) and pushing through the filament. Once it passes through the assembly wiggle the motor around to get it to line up with the barrel. You should feel it as the filament aligns with the barrel and passes into it. Once this happens you are now ready to tighten the mount screw (refer to Figure 6).
Once the mount screw is tightened then reconnect the wiring plug (refer to Figure 5). Now you are ready to put on the heat sink, the two nylon spacers, and insert the screws for the fan. Make sure when putting on the fan that the wording on the fan hub faces into the extruders. Or in other words, you should not be able to see the wording on the fan if placed in the correct position (refer to Figure 4). Additionally, the fins on the heat sink should be facing outwards or you should be looking into all of the fins. The two nylon spacers should go between the heat sink and the fan. The order that the screw should pass through is 1. Fan Assembly, 2. Nylon Spacer, 3. Heat Sink, 4. Aluminum Block.
Now you are ready to reassemble the carriage. Place the extruder assembly back into the carriage and insert the two carriage screws (see Figure 9) and tighten.
Now load filament and print away!
I hope this helps to resolve any issues you may encounter, but it will not fix every jam you may encounter. So, if you experience a different type of jam (not Grape or Apricot) or clog, please post what you experience and how you fixed it. That way we can all learn a little!!
– Dave Weas, Imaginator3D Team