Creality K1 Max D3D Bed Fans

Note: this was tested using a 6mm thick bed with a Keenovo 750w heater. With the stock bed/heater you may see less effective results.

You can use 1 or 2 sides to help with chamber heating. Uses 5015 24V blower fans. Can be connected to the exhaust fan or utilize PIN4 on the stock K1 board (there is one empty fan spot). I printed as the pic indicates, for me this produced the best quality print.

Grab the PCB from Fabreeko to make connecting the fans super easy. Print the JST Splicer Mount (credit to BootyJones) that mounts easily underneath the bed and connect the fans easily. 

I used this tape to hold the wires in place under the bed: Heat Resistant Tape

If you want to wire this up using the spare PIN4 on the K1 board:

Add this as a 4th pin in printer.cfg(need root):

[output_pin fan4]
pin: PA0
pwm: True
cycle_time: 0.0100
hardware_pwm: false
value: 0.00
scale: 255
shutdown_value: 0.0

and in the slicer add custom start print gcode (under Filament for ABS / ASA):

SET_PIN PIN=fan4 VALUE=175 #255 is max, recommended is 150-200

and set value=0 to your end print start gcode