Lulzbot Mini Extruder v2.1 dual fan modification

thingiverse

Lulzbot Mini printer lacks space for dual fan configuration like TAZ, so I created an easily attachable secondary fan. When print job is small enough, I can attach it without issues. However, bed auto leveling process must be completed before attaching the fan. End stop trigger on removable fan prevents collision during each print session. Be cautious: large print jobs with attached fan may cause damage! Secondary fan is secured with 5 cylinder magnets measuring 6 x 3 mm. Extruder mount features wiring harness to guide power cables to secondary fan mounting point. Fan is powered through two magnets. I recommend the 65-degree version: - 68 degrees: Lulzbot extruder v2.1 has different tilt angle for fan, possibly more effective at higher speed. However, maintaining 240 C temperature becomes challenging with dual fans. - 65 degrees: I modified extruder mount to original angle (green printed parts). This eliminates excessive cooling and provides better compromise than 68-degree version. When soldering wires to magnets, protect the magnet from losing magnetism during heating by placing a stronger magnet underneath. I used spherical magnet to avoid heat conduction and then placed a bigger cylinder magnet underneath for added protection. I also created a heatsink fanduct modification, as my fans are too powerful for cooling the heatsink. By guiding half of the airflow to the stepper motor, I reduce concerns about stepper motor lifetime when printing in a heated chamber.