Standard Air-duct for the Shell of a 40x40 blower

thingiverse

I designed it for my Prusa i3 (Lion-S model), but the blower shell is a standard part. Instructions I wanted a shorter pipe to prevent it from hiting the being extruded object, and I also wanted it to be less noisy than the one supplied with my printer which had too tight lips. So I used Fusion 360, drawing first a planar sketch of the side shade, then some extrusion, and then used the shell function for the inside hollow.