Update (2017|03|19) I added a new version, nozzlecooler3.stl, that has walls on the inside to make the air reach every hole. Also, it has some led mountings on top that can be disabled in OpenSCAD source code.
A nozzle cooler for my Anycubic I3 printer. I built it from scratch using OpenSCAD, but I got inspiration from this thing. The entire object is free (GPL). I rendered the .stl files at
$fn=150 and it took about one hour and 10GB RAM - but at this size I cannot see the different cylinders I used for the ring (at
$fn=50 I can see them) when printed.
Assembly: Simply put part 2 on top of part 1 so that the holes match and the pin of part 1 is in the hole of part 2. Screw the fan on top of both parts and it should fit perfectly.
Might work on other printers as well