This provides a wedge that can be used to mount a small fan at an angle. For example, I prefer to install the cooling fan for my e3dv6 hot end in a flipped configuration that exhausts warm air out the fan instead of through the back of the hot end. A 10-degree wedge is used to help orient the airflow upwards a bit to help keep it off the print surface.
Two STL files are provided. File 30mm_10degrees.stl provides a 10-degree wedge that can be used with a typical 30mm fan. File 40mm_10gegrees.stl provides a 10-degree wedge that can be used with a typical 40mm fan. Other configurations can be obtained by tailoring parameters in the openSCAD source.
The gallery picture shows a print of the 30mm_10degrees.stl wedge installed with the OEM duct on the e3dv6 hot end. 16mm and 20mm long M3 screws were used to install the fan and wedge on the duct. The fan is shown installed in the flipped orientation.
It might take some encouragement to thread M3 screws into the duct. For a new duct, thread and remove the e3d screws into the duct first to open up the holes in the duct a bit. Tapping the holes in the duct for M3 may help prevent splitting at the corners on the duct lip.
See the comments at the beginning of the openSCAD file for more information and detail.