Please read the cautions.
This model was tested and printed on a K1C (without support).
I used an Arctic P8 Silent fan (80 mm x 25 mm) + LX8015 DC-DC Adjustable Step-down Converter because the fan is 12v. The fan is way more quieter then the standard one and offers more airflow for cooling.
The safest way is to use a 24v 3-pin fan because you don't have to use the step-down converter!!!
You will need:
The fan was connected to -out and +out of the converter and the sensor wire directly to the motherboard.
CAUTION!!!
The author remixed this model.
Changed the model to accommodate an 80mm fan.