Prusa 60mm hot end fan duct by Phizinza

thingiverse

You'll find similar designs inspired by richgain's version, with two components - the duct and bracket. This design is compatible with Greg's extruder, providing approximately 16mm of adjustability in height for various hot ends. However, note that this may not work with Prusa V2; please refer to comments. The airflow is ducted at about 30% on the side where the fan is located and 70% around the revolve to blow from different directions. A 60mm fan was used due to availability. To print this, your printer needs to have good bridge-printing capabilities. Initially, you may need two fans blowing from different angles for successful printing. The bracket replaces x belt holders and might require "teeth" for grip if you design your own. Assemble the duct and bracket with a couple of 3mm bolts and nuts. For issues with the initial inner ring not staying connected to the heatbed, try Dracus89's version with a .5mm fill on that first ring, which needs cutting out after printing for hotend passage.