Video and more pictures: https://buzzheavier.com/lwrmtq6pz4lu
Originally a shower rack, I removes the wheels and fastened it to my TV shelf with wires. The fans of the single board computers where so loud and ineffective that I removed then and instead installed six of Noctua’s cheapest chassi fans. After a while, I noticed that dust builds up, so I fastened these grease filters with some Velcro. Easy to take off and clean. I know it looks ugly as they are weighed down in the corners, but their purpose is to catch dust, not to walk the red carpet. 😎
The metal will block some Wi-Fi signals, but not completely, because the gaps between the bars are too wide to block it all.
2.4 GHz also happens to be the frequency that microwaves operate at. Every microwave oven has that mesh in its window, because those holes are precisely the right size to let you look through while still blocking all the 2.4 GHz emissions inside the box.
If this site isn’t bullshitting me, then the 60-ish millimeters wavelength of the 5GHz band passes through the gaps between the bars with ease too. :)
https://www.everythingrf.com/rf-calculators/frequency-to-wavelength