Simple 1405 extruder fan mount

This is a remix of an existing extruder fan mount (see remixes) that

didn't fit the simple 1405 and that had a tendency to fall off.

I cleaned up the geometry (removing some of the extra vectors), removed some material that was preventing it from fitting on the 1405, and added some additional material to give it more traction when gripping the printer.

This is a friction mount so make sure you press it on well or it will fall off.

Update - I used up some of the extra space next to t