Robo3D R2 40mm Extruder Fan Cooler

Designed to improve the cooling and control of the hotend fan. Please read the below to fully understand how I've fitted this.

The R2 always runs the extruder cooling fan even if its not printing. This mod has enabled me to now control the 40mm fan so it only turns on if the nozzle is above 50 degrees C.

PLEASE NOTE - You have two choices, you can either use a 12 volt fan and plug it in the center fan power socket. OR a 24 volt fan and plug it in the Extruder 2 socket. Only the 24 volt f