K2 Plus: a clump or blob of filament forms around the hotend
Guide based on the manufacturer's official documentation; usi3d has not yet verified it on a machine.
Technology: FDM · Brand: Creality · Symptoms: Does not stick to the bed, Blobs and zits on the surface · Updated on 9 October 2026
Symptom
On the K2 Plus filament builds up around the nozzle and hotend into a lump that can wrap the nozzle cover, the fans, the nozzle camera or the hotend board. It usually starts when the part detaches from the bed and the nozzle keeps extruding in mid-air.
Likely causes, from most to least likely
- The material in the sliced file does not match the loaded filament (for example sliced for PLA but printing ABS): wrong temperatures and the part does not stick.
- The plate is dirty or greasy and the part comes loose.
- Cold room: below 15 °C parts stick worse.
- Small parts or parts with little contact area that come loose easily.
- The bed is not levelled or the first layer settings are not suitable.
Checks to tell which one it is
- Compare the filament selected in the slicer with the one loaded.
- Check the plate: fingerprints, grease or residue.
- Check the room temperature.
- Assess the damage: if the lump covers the hotend board, the heat break fan or the nozzle camera, they may be damaged.
Before you start
Before taking anything apart, cleaning or adjusting it, switch the printer off and unplug it, unless a step says otherwise, and do not touch the nozzle, the heater block or the bed until they have cooled down. If in any doubt about electricity, heat or moving parts, stop and ask a professional.
Step-by-step fix
Prepare the printer
On the control screen unlock the motors, lower the platform fully and move the extruder to a comfortable position. Remove the nozzle cover; if the lump traps it, it may have to be broken.
Check: You can reach the lump around the nozzle.
If that does not fix it: Soften the lump with heat (next step).
Soften the lump with heat
Raise the nozzle above the recommended temperature for that material: for PLA, printed at 190-230 °C, Creality suggests 250 °C. Wait about 5-8 minutes for it to soften.
Check: The built-up plastic is soft.
If that does not fix it: Wait a little longer before pulling.
Remove the lump
Wearing heat-resistant gloves, or with cutting pliers, remove the lump by moving it side to side or back and forth. Do not touch the nozzle: it is hot.
Check: The large pieces are off.
If that does not fix it: Remove the hotend to clean the rest (next step).
Cool down and remove the hotend
Set the nozzle to 30 °C and wait for it to cool (a hair dryer on cool helps). Cut the filament by pushing the cutter with a wrench or screwdriver, remove the four hotend assembly screws, carefully unplug the hotend and thermistor cables and take it out.
Check: The hotend is out and cold.
If that does not fix it: If the heat break fan is trapped, cooling will be slow: be patient.
Clean and check for damage
Clean the residue off the heat break fan, the hotend board and other areas, taking care not to break them. If the hotend is badly damaged, replace the whole assembly. Also check the hotend adapter board, the part cooling fan, the heat break fan and the nozzle camera.
Check: No residue is left and the parts are intact.
If that does not fix it: Replace damaged parts following Creality's guides.
Reassemble and calibrate
Refit the hotend, connect the hotend and thermistor cables properly and put the cover back. With no filament in the extruder, choose «Pattern Optimization» on the calibration page and wait for the self-check to finish before printing again.
Check: The self-check finishes without errors and the printer heats normally.
If that does not fix it: Contact Creality support.
Prevention
- Always slice with the same material you are going to load.
- Clean the plate with alcohol, detergent or a degreaser, or apply a thin layer of the included glue stick.
- Below 15 °C room temperature, raise the bed by 10 °C, and add a skirt to small or delicate parts, as Creality advises.
Still not fixed?
Tell usi3d's AI about your case: choose your printer, describe what you see and add photos if you like. It proposes checks step by step, with their sources.
Printers it applies to
Creality K2 Plus.
Official sources
This guide summarises the official documentation linked here:
- Troubleshooting for K2 Plus Hotend Clumping · Creality
- Troubleshooting for K2 Plus Non-stick Platform · Creality
- Replace K2 Plus Hotend · Creality
This guide is general information: usi3d has summarised it from the official documentation linked here, and it may not match your model, its version or its firmware. If in doubt, follow the manual and the support of your printer's manufacturer. You decide what you do with your machine, and working on it may affect its warranty.