Prusa Box Enclosure - Einsy motherboard cooling duct with Noctua fan

Inspired by Colin (https://www.printables.com/model/109599-prusa-box-enclosure-einsey-motherboard-cooling-duc) I made my own version which is able to fit the Noctua A4x20 20mm tall fan. This duct works well if the printer has the elastomer feets sold on Prusa-Box's website.

I've also made two grills:
- one for fixing the fan with screws (it has countersink holes)
- one for fixing the fan with the NA-AV3 rubber anti vibration mounts (countersink from the other side)

There are 4 version of the duct, they have the hole for the cable on different places.

Needed for the assembly:
- 4 pieces of DIN562 M3 square nuts
- 4 pieces of M3x10 or M3x12 screws

Assembly:

1. Mount  the fan with screws or the NA-AV3 to the grill
   • Cut the unnecessary parts of the NA-AV3 after assembly
2. Push in the square nuts to the duct
3. Push the fan+grill inside the duct from below
4. Put this sandwich on the inside of the box, mount it with screws from below