7.5L 4-Bay ITX NAS Case (External PSU)

This is another variant of the original 4-Bay Hot Swap NAS case that uses the same modular HDD Cage and backplane system as my other designs. The goal of this design was to make the smallest possible case with a standard ITX motherboard upon request of another reddit user.

To power this system, you'll need an external 12v/19v supply with either an ITX board that supports external power or an appropriate Pico-PSU if you're planning to re-use a standard gaming motherboard.

The HDD sections all screw into the mounting holes of the HDD cage to provide rigidity to the case and the motherboard cover uses a cleat design to slide onto the HDD Frame part to cover the screws and mount securely. Printing the motherboard cover will require some supports but the rest of the parts are designed to be printed with the major flat surfaces on the print bed thus removing the need to support.

The airflow path on this case was a bit complicated since the ITX board basically blocks any through flow from the bottom fan so I recommend adding a mesh to the inside of the front panel and making that the filtered intake with both the top and bottom fans acting as exhaust fans to maintain a negative pressure inside the case. In my testing with other similar designs, the fans are more effective at pulling air than they are at pushing air even with high static pressure fans.

This case can be used in whatever orientation your heart desires but there's builtin screw holes for mounting feet at the bottom of the case where the main IO is located. I didn't re-design the IO orientation since I wanted the front panel design to be compatible between all my designs for when I get around to finishing the mounting for the USB ports there.

Full disclosure, I haven't print-tested this model since it doesn't fit my personal NAS requirements but please share any feedback so I can adjust tolerances as necessary to make this design work.