Anycubic i3 mega extruder stepper fan holder aiming at filament (with or without ON/OFF switch)

thingiverse

Following several broken PLA filaments due to excessive temperatures at the extruder stepper level, I designed a custom holder for a Noctua NF-A4x10 FLX fan to blow air directly onto the filament. As a result, the filament stays cool, and I've never experienced any further breakage since making this modification! I incorporated a convenient spot to attach an ON/OFF switch, allowing you to toggle the fan's operation on or off when not in use. This feature prevents the fan from running continuously while the printer is powered up. This design can be used in conjunction with a filament gear knob (available at Thingiverse under ID 2747964), although it may slightly impede air flow onto the filament. Nevertheless, it should still provide adequate cooling performance. The holder's functionality remains unaffected even when installed within an enclosure; however, I haven't tested this scenario and would caution against using it with ABS plastic due to potential airflow limitations.