¶ Applicable Scenario
-
The printer reports extruder motor overload, air printing, or no error but it can be observed that the hotend is unable to extrude filament.
-
Printing with non-TPU filament.
¶ Possible Locations of Clogging
-
Extrusion components (including the extruder idlers, gap between the drive gear and extruder idler, and extruder filament guide)
-
Hotend
¶ Troubleshooting Steps
Before troubleshooting, please retry once to see if printing can be restored normally. If the issue persists, then proceed with the following troubleshooting steps.
¶ Step 1. Heat the hotend
Open the front door of the printer, remove the top cover. Then pinch both sides at the top of the toolhead front cover and remove the toolhead front cover; press the black outer ring to disconnect the PTFE tube. And heat the hotend to 175°C.
The prerequisite for controlling the rotation of the extruder gear is that the hotend temperature is above 170°C. Therefore, we recommend setting the hotend temperature to 175°C for easier control.
¶ Step 2. Manually unload the filament
Wait for the hotend to reach 175°C, assist by gently pulling the filament by hand, and slowly click the retract button on the screen (do not click too quickly to avoid more clogs or filament entanglement). You could feel if the filament is moving. If the filament is retracting, continue to fully remove it.
If any abnormalities are noticed in the retracted filament, such as a swollen filament end, cut off the problematic section of filament approximately 15 cm, then reconnect the PTFE tube and resume printing.
If you are unable to manually pull back the filament at this step, or if after following these suggestions and reloading the filament, the extrusion issues persist. Then please proceed to step 3.
-
It is recommended to keep the front door and top cover open during printing, and remove the front cover of the toolhead to improve heat dissipation, which helps prevent such clogging issues;
-
It is advisable to reduce the print speed appropriately;
-
Investigate the quality of the filaments themselves, and consider trying a new spool of filament to see if the issue persists.
¶ Step 3. Wait for the hotend to cool down and remove the hotend
Set the hotend temperature to 0°C, wait for the hotend temperature to return to room temperature, then cut the filament. Please make sure to wait until the temperature has reached room temperature before cutting the filament to avoid potential secondary clog at the cutting point.
Next, remove the silicone sock, release the hotend latch, and then remove the hotend.
¶ Step 4. Reheat the hotend, and manually extrude the filament
On the screen, reheat the hotend to 175°C.
Wait for the hotend to reach 175°C, assist by gently pulling the filament by hand. Slowly press the extrude button on the screen (do not click too quickly to avoid more clogs or filament entanglement). Feel if the filament is being gripped and pulled down, and observe if any filament is being extruded from the extruder filament guide.
If the filament can be successfully extruded and any abnormalities in the extruded filament are observed, please cut off the abnormal section of the filament by 5 to 10 cm. We recommend opening the front door and top cover during the printing process, as well as removing the front cover of the toolhead to improve heat dissipation and prevent such clogging issues.
Ensure improved heat dissipation for the extruder components (open door, remove the front cover). Set the hotend temperature to 0°C on the screen and wait for the temperature to drop to room temperature. Then, reinstall the hotend and load the filament again on the filaments page to resume printing.
After resuming printing, observe whether the extruder gear is rotating normally and if any filament is being extruded from the hotend. If the extruder gear is rotating properly but no filament is observed extruding from the hotend, follow this wiki H2D Hotend Unclogging Procedure to clear any clogs in the hotend.
¶ Step 5. Remove the extruder filament guide for cleaning
If in step 4, with the hotend already removed, the filament still cannot be successfully extruded, it indicates a clog inside the extruder assembly. In this case, the extruder filament guide needs to be removed to clean the clog within the extruder assembly, including the extruder idler, the gap between the drive gear and extruder idler, or extruder filament guide.
It should be noted that there is interference between extruder filament guide and the left and right cutter levers, making disassembly and assembly somewhat challenging. This difficulty is especially pronounced when a segment of filament passes through both the extruder gear and extruder filament guide simultaneously (in dual-color printing, there might be two segments passing through the left and right sides simultaneously). Despite the increased challenge in disassembly and assembly, please do not be discouraged. By following the suggestions below, you will be able to successfully remove the extruder filament guide.
Ensure the hotend is at room temperature, remove the hotend not blocked by the flow blocker first, then switch the extruder on the screen to remove the other hotend as well.
Remove the four screws on the extruder filament guide, push up the black hotend connector forcefully with your fingers to allow the left cutter to come out slightly from the open slot near the cutter screw. Then, lever out the extruder filament guide from the lower right corner. In this scenario, there is usually a segment of filament passing through both the extruder and the extruder filament guide, requiring significant force to remove the extruder filament guide. After removing the extruder filament guide, cut the filament between the guide and the extruder to separate the extruder filament guide.
If the black hotend connector is obstructed by filaments or springs, preventing it from being pushed up to avoid interference, or if you encounter significant resistance while removing the extruder filament guide, you may add an additional step. Remove the levers of the left and right cutters before taking out the extruder filament guide. During the subsequent reassembly, refer to this wiki to reinstall the cutter levers: H2D extruder unit disassembly and assembly.
After successfully removing the extruder filament guide, please proceed with cleaning as necessary based on the actual situation:
¶ Scenario 1: Abnormal filament may be stuck in the gap between the extruder drive gear and extruder idler.
For this scenario, there are two methods to clear the clog.
- Cut the filament above the extruder, grip the clogged filament with tweezers or needle-nose pliers, and exert downward force. Simultaneously, switch the extruder on the screen and release the filament when switching left and right on the extruder to create a gap, allowing the filament to be removed.
- Cut off the abnormal part of the filament, then heat the hotend to 175°C. On the screen, press the retract button to remove the remaining normal filament.
In severe cases, the filament may get tangled or caught inside the extruder gear, making it difficult to directly pull out or retract the filament. In such instances, refer to this wiki to remove the extruder front cover or gear for cleaning: H2D extruder unit disassembly and assembly
¶ Scenario 2: The abnormal filament may be stuck at the extruder filament guide entrance or inside it.
If the abnormal filament is only stuck at the extruder filament guide entrance, you can simply use needle-nose pliers to pull it out.
If the abnormal filament is clogged inside the extruder filament guide, you will need to disassemble the extruder filament guide for cleaning. Loosen one screw first, then remove the black hotend connector along the guide rail, and detach the cutter and spring.
Use an H1.5 Allen key to clear the interior of the black hotend connector and extruder filament guide to prevent any filament from remaining blocked inside.
After cleaning, put the spring back on the black hotend connector, and reinstall the connector along the guide rail, ensuring that the spring fits snugly onto the slider in the red frame. Then, reinstall the screw and put the cutter back. It is important to note that the cutter has one concave side, so make sure the concave side is facing upwards when inserting the cutter.
¶ Scenario 3: Abnormal filament may be stuck at the exit or inside of the extruder idler.
This situation is very rare. If it occurs, it is recommended to use an H1.5 Allen key to attempt to push out the filament. If unsuccessful, refer to this wiki to replace the extruder idler: H2D extruder unit disassembly and assembly
When installing the extruder filament guide, first press firmly upward on the black hotend connector. Then, gently press the cutter to adjust it to an appropriate angle before inserting the extruder filament guide. Finally, press on both sides of the cutter while applying force to completely flatten the guide surface.
Then re-tighten the four screws on the extruder filament guide.
After cleaning is complete, reinstall the hotend and lock the hotend latch, then reinstall the silicone sock for hotend. Switch the nozzle on the screen and install the other hotend using the same method.
Reconnect the PTFE tubes, with the PTFE tube above the drag chain connecting to the right extruder and the PTFE tube below the drag chain connecting to the left extruder.
When reinstalling the toolhead front cover, first latch it under the extruder and then push it back to secure the front cover in place.
¶ End Notes
We hope the detailed guide provided has been helpful and informative.
If this guide does not solve your problem, please submit a technical ticket, we will answer your questions and provide assistance.
If you have any suggestions or feedback on this Wiki, please leave a message in the comment area. Thank you for your support and attention!