Sometimes the extruder gear is clicking or skipping. This can affect the quality of your prints and cause under-extrusion, blobs, or gaps in the layers. This can be difficult to diagnose because the root cause is often at the other side of the printer.

The extruder gear is the part that pushes the filament into the hot end, where it is melted and deposited onto the build plate. The extruder gear has teeth that grip the filament and rotate to feed it. Sometimes, the extruder gear can click or skip, meaning that it slips on the filament and fails to push it forward. This can happen for several reasons, such as:

• The nozzle is too close to the build plate, causing too much back pressure and preventing the filament from flowing out.
• The nozzle is clogged or partially blocked by dirt, dust, or debris, reducing the flow of filament.
• The nozzle temperature is too low, making the filament too viscous and hard to extrude.
• The filament diameter is inconsistent or out of spec, causing variations in the extrusion rate and pressure.
• The filament is tangled, kinked, or twisted, creating friction and resistance in the feed path.
• The extruder tension is too high or too low, making the extruder gear either slip on the filament or crush it.

To fix the extruder gear clicking problem, you need to identify the root cause and address it accordingly. Here are some possible solutions:

• Adjust the nozzle height and level the build plate, making sure there is enough gap between them for the filament to flow out smoothly.
• Clean the nozzle and check for any clogs or blockages. You can use a needle or a wire to poke through the nozzle hole or perform a cold pull to remove any stuck material.
• Increase the nozzle temperature slightly and see if it improves the extrusion. You can also try a different filament material or brand that has a lower melting point or better flow characteristics.
• Measure the filament diameter with a caliper and make sure it is within the tolerance range of your printer. You can also adjust the extrusion multiplier in your slicer software to compensate for any variations in the filament diameter.
• Check the filament spool and make sure it is not tangled, kinked, or twisted. You can also use a filament guide or a spool holder to reduce any friction or resistance in the feed path.
• Adjust the extruder tension and make sure it is not too tight or too loose. You can use a screwdriver to turn the tension knob or spring on your extruder assembly. You want to find a balance where the extruder gear grips the filament firmly but not too hard.