Design: https://www.thingiverse.com/thing:2808152
I just wanted to share this design (I am not the author), because I think, it is the single best cooling solution for evenly cooled prints.
You might have noticed that with a directed print fan, overhangs eventually end up messy.
In my case the 270° version of the design fixed this issue well.
The fan in the pictures (blue) was btw printed by an identical smart effector/fan setup...
