CPU

This section is optional. If you are not using a SoC CPU like a Raspberry Pi, use a fourth side panel in the next assembly section.

Overview

Materials

As IllustratedGeneric

Parts	Qty	Note
M3 x 6mm machine screws	4
M3 x 8mm machine screws	4	May substitute 10mm or 12mm.
M3 x 15mm machine screws	4	May substitute 16mm.
Raspberry Pi 4B	1
40mm x 10mm Axial Fan	1
Assembled SPI cable	1
Universal Raspberry Pi CPU Tray	1	Printed

Parts	Qty	Note
M3 x 8mm machine screws	4	May substitute 10mm or 12mm.
M3 x 6mm machine screws	N/A	Most SoC CPUs use four (4).
Compatible SoC CPU	1
CPU Tray	1	Printed

Warning: M3 x 16mm screws

If using M3 x 16mm screws for the 40mm fan, do not overtighten or you may deform the outer panel surface.

Note: SPI cable

The illustrated CPU tray has a cutout for a 2 Row, 6-position Molex Micro Fit 3 connector. This cutout can be wired to connect devices to the SoC CPU, such as an accelerometer.

Assembling and wiring this cable is beyond the scope of this guide, but the cable can be made from DuPont-terminated breadboard wires.

Directions

1. Orient the 40mm fan and fasten with four (4) M3 x 15mm screws. If substituting with 16mm screws *do not overtighten.

2. Place the Raspberry Pi on the tray. The headers should face away from the fan.

3. Fasten with four (4) M3 x 6mm screws. The holes are for M2.5 screws but will bore out easily for M3 screws.

4. (Not pictured) Connect the SPI cable to the Raspberry Pi GPIO headers. Double-check that the cable pins mate to correct the headers.

5. Snap the Micro Fit 3 connector into the CPU tray panel.

6. Slide the CPU into the case. In this example, we use the front right CPU bay.

7. Secure with four (4) M3 x 8mm screws.

Reference