r/CrealityK1C

New K1C. Fourth print had heavy stringing, Fifth stopped extruding partway through. Clicking, then nothing.

Tried: 240°C retract/extrude, removed the extruder and cleared stuck filament, cleaning needle passed freely through the nozzle. After reassembly it ticked but wouldn't feed. Tested the extruder off the printer — turned the gears by hand with a short piece of filament and it gripped and fed fine. Mounted back on the printer, ticking again. Never fed properly after that.

Room has no AC and I ran it fully enclosed.

Amazon sent a replacement, still boxed. Trying to decide whether to open it or refund and get an A1.

• If you've owned both, which held up better day to day?

So, I have been having issues with both the K1C and the K2 Plus at my job. The issue started around the same time with both printers, and I haven't been able to figure out how to fix my issue. So, it's essentially the exact symptoms of heat creep where the filament melts at spots higher and higher up the nozzle until it melts and jams at the very top of the nozzle. I have replaced the hot end, heat sink, cooling fans, extruder, extruder motor and I'm still having the issue on both of them. I have been in contact with Customer service, but I haven't gotten anywhere with them.

I have also taken a Laser Temp gun to check the temperature of the hot end after about 30 minutes of printing, and the top of the heat sink was at around 85 degrees.

The nozzle usual fills up with filament and starts to jam at about the hour mark and I did a test print where I started the print with a brand new nozzle and let it print until it started to clog and under extrude, then I paused the print for 10 minutes or so and then resumed the printing and it started printing fine again. any help or insight is greatly appreciated.

I am printing with CR-PETG with a nozzle temp of 250c and a bed temp of 70c

Does anyone know what is causing this and how to fix it. I swapped the extruder gears as there was a tooth missing.

0.2mm

190C

300mms

https://preview.redd.it/lk866lgx2ujh1.png?width=2160&format=png&auto=webp&s=7175a0fbbded4e1d53446864ad69f8783267ffc8

https://preview.redd.it/696aat4y2ujh1.png?width=2160&format=png&auto=webp&s=c6b022f0db496390c2a8fc275c86c1989fba80bd

When I installed the new extruder on my K1C 2025 model, I connected the sensor cable to the nozzle MCU and didnt worked.

The cable pins from the DXC filament sensor are swapped because Creality changed the order of the pins in the Nozzle MCU for the 2025 new model.

You need to accommodate the cables from the sensor connector in the correct order:

https://preview.redd.it/633ppf50yaih1.png?width=1600&format=png&auto=webp&s=8630b1a69b7e31f1caa091d1a5ffe66a5859fd2c

https://preview.redd.it/lg3p9f50yaih1.png?width=720&format=png&auto=webp&s=3b9c41f58d005d877d545a9f8b642fe010ffe539

After that, you need to modify your printer.cfg

First comment old sensor settings

#[filament_switch_sensor filament_sensor]
#pause_on_runout: true
#switch_pin: !PD7

Add the new settings for DXC sensor

[filament_switch_sensor DXC]
pause_on_runout: true
switch_pin: nozzle_mcu:PB9
event_delay: 1.5
pause_delay: 0.25
insert_gcode: 
  M118 Filament inserted
runout_gcode:
  M118 Out of filament
  {% if printer.extruder.can_extrude|lower == 'true' %}
    G91
    G1 E-30 F180
    G1 E-50 F2000
    G90
  {% endif %}

[respond]
default_type: echo
default_prefix: 

I got PB9 from Nozzle MCU chip datashet, is the pin number 46 where is connected the signal from filament sensor. Also removed the "!" because with it, the results were swapped.

Save and restart printer and the sensor will work. You can now query in console
QUERY_FILAMENT_SENSOR SENSOR=DXC

And you will get something like this:

https://preview.redd.it/a534eqw2yaih1.png?width=545&format=png&auto=webp&s=7616f9375e861dcb2627e308bed329b603c3ff5e

Note:
To edit printer.cfg in your K1C 2025 model, you dont need a rooted printer, just go to https://app.fluidd.xyz/ or install fluidd in your computer, and add your printer as PRINTER_IP:7125 (example 192.168.33.134:7125) and then you will see the printer.cfg to update it.