Raspberry Pi Zero Cooling Fan Bracket

The Quad-CPU Raspberry Pi Zero 2W is a pretty powerful beast for its size. However, if not properly cooled it will throttle its CPUs at about 80 deg C: https://raspberrytips.com/raspberry-pi-temperature/

This fan assembly helps you to push the Pi Zero 2W to its limits, in particular if you are running it at high ambient temperatures and/or applying overclocking. It fits the Pi Zero W and the Pi Zero as well.

It is an improvement over my previous design https://www.thingiverse.com/thing:6500953. You will find there some Python programs to monitor and control the CPU temperature. Some electronics and soldering will be required to on/off-control a two-wire fan via the Python program fan.py . Variable-RPM three-wire fans are not supported by my electronics and software.

In my previous design the fan motor's back is shadowing part of the heat sink, limiting the cooling effect. This new improved design is directing the fan's air more efficiently over the Zero CPU's heat sink.

On one of the print parts you will require a support pillar (see picture).

I added two front bracket variants 3 and 3a where you simply push the assembly over the GPIO pins instead of screwing it to the PCB via the Pi's mounting holes. As a downside this will keep you from accessing some of the GPIO pins. Version 3 and 3a (the latter without nose cone due to printing restrictions) will block different GPIO pins to give you a choice.

Apart from the Pi Zero and the printed parts you will need

• The ubiquitous 14/18x13x6 mm heat sink with double-sided sticker tape on its back, e.g. from https://en.aliexpress.com/item/4000515928855.html . The CPU positions on the various Pi Zero types differ by a mm or two. You may have to optimize the heat sink's position depending on your Pi Zero's type relative to the position of the bracket's hood.
• A high-rev 5 Volt two-wire 20x20x10 mm fan, e.g. this 15'000 rpm beast: https://en.aliexpress.com/item/1005002554588949 . If the fan is generating excessive noise after a prolonged period of use (usually several thousand hours), remove the nameplate on its back and deposit "half a drop of oil" on the bearing to give it a new lease of life.
• Three M2.5 x 16 mm screws to mount the fan between the two brackets
• Two M2.5 x 8 screws and two M2.5 nuts to screw the assembly to the Zero

The printed parts' mounting holes have diameters of either 2.5 or 2.0 mm, depending on whether they are meant as 2.5 mm bores for just pushing the M2.5 screws through or 2.0 mm bores for the M2.5 screw cutting its thread into them upon first insertion. See pictures for the proper insertion of the screws.

As always I am including the OpenSCAD source file for you to adapt and/or improve:

• Install OpenSCAD from https://www.openscad.org
• Launch OpenSCAD and open the enclosed OpenSCAD source file (/File/Open).
• Amend the parameters at the top of the file or even amend the code.
• Save your changes (/File/Save).
• Render the design (/Design/Render).
• Export the rendered design e.g. as a .stl file (/File/Export/Export as STL).
• Slice and print.

See my other designs at
https://www.thingiverse.com/thinger13/designs