Built and mixed from many other fan parts.
FOR 40 mm FAN and gregs extruder.
I recommend printing with PLA 1.75 at 0.20 layer height and 33% infill. I used kisslicer but prints well with slic3r too.
You'll need to glue the two tinny parts in order to adjust and fix the angle needed for your printer.
Uploaded version 4 STL files, improved.
Recommended print for kisslicer:
3 perimeters per layer
0.20mm layer height (no more than 0.30!)
set infill between 20 and 50% (recommended 33%)
My tests worked fine with 1.75mm PLA and 40 mm fan.
This is a fan mount for 40mm fan and gregs extruder.