This is a cooling fan back cover plate I made for the Official Raspberry Pi 7" LCD Case.

Here is a link to the fan I used on Amazon:

https://www.amazon.com/dp/B072FW3DDQ/ref=cm_sw_em_r_mt_dp_U_YefOCbTA0TSVM

If you already have the LCD plugged into the 5v GPIO pins 2 & 6, you'll want to connect the fan to the much quieter 3v connection. Plug the fan into pins 1 & 9, red on 1, black on 9. Pin 1 is on the top left next to the red one that's already plugged in, and 9 is the fifth pin down on the same side.

In the example picture, I have it plugged into the second 5v connection. I changed it after a few days because it was way too loud and too powerful for what I was using it for. The 3v connection is perfect, IMO.

For hardware you'll need:

4- M3x12mm bolts.

4- M3 nuts.

I printed it just like it is in the STL file, rounded side up. I used line infill at 10% for the pegs and the fan hole.

Print Settings

Rafts:

No

Supports:

Yes

Resolution:

0.2

Infill:

Line 10%