Tired of the loud noise of the always on cold-end fan i designed this fan duct to replace the stock 30mm fan with a super quiet 40mm Noctua fan (should fit all 40mm fans).
Since i already had a 12v fan i had to use a "step down converter" to bring the 24v down to 12v. You could also buy a 5v fan (noctua makes one but it's sligtly louder) and plug it in the unused 5v pins instead of the stock location.
The stock screws must be replaced with shorter ones or cut to lenght
The Metal plate covering the fans has to be cut
I suggest printing this with supports
I also included the original f3d file for you to modify if needed