What if the fan is too thin to be properly seated within a Raspberry PI Case ?
Simple, use Aquarium 5mm tubing for DIY washers!
Having ordered two RPI cases without fans and buying the fans separately, I discovered that the fans (although quiet at 3.3V) were not tall enough to be fixed within the case. The four plastic standoffs were longer than the fan and even with the screws in place, the fan would just rattle. Also, the screws shipped with the fan were also too thick for the case.
Wondering how I can fix the fan so that it doesn’t vibrate, I had the idea to create few washers and spacers out of aquarium 5mm flexible tubing. I think the photos speak for themselves:
Decided to use the computer case analogy where the fan expels the air. Without any radiators (using a Raspberry PI 3B+ board which has a mini heat sink already applied), the temperatures have dropped with 10C as is visible below (screenshot from the Graphite). Software was the same, basically an idle LibreELEC:
Also, the fan is quiet at 3.3V (unless you put your ear close to the case) so mission accomplished!