Carbon Hepa Fan Sandwich

My take on an activated carbon / hepa filter / air recirculator for my printer enclosure.

I wanted a filter system that could be easily maintained and that would be flexible in configuration and something that I could add or remove easily from the enclosure (it usually just sits in the back).  No screws are needed.  This uses 6mm x 3mm magnets to hold all the pieces together with a little super glue (Though be careful with the activated charcoal section…I haven't had any accidents yet).

The fan is sandwiched between the HEPA filter and the activated carbon; however, it's flexible enough that you could omit either piece or you should be able to put them both in a push or pull configuration (make sure the magnets are aligned the same direction).

• Fan: I'm using a Noctua NF-A14 iPPC-3000 PMW connected directly to my main board.

• HEPA filter options:

  • A single vacuum HEPA filter (https://www.amazon.com/s?k=EL012B)

  • 6 smaller HEPA filters (https://www.amazon.com/gp/product/B0782T7L6P/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1)

• Activated Carbon: Nevermore Activated Carbon

Magnet size is set to 6.25 for my tolerances.  The Fusion design is attached and it can be changed in the parameters.

2026-05-05 Update: Created Fan Box V2 that provides a 5mm gap on both sides of the fan (Bottom is a few mm thicker and then the fan insert area is 5mm deeper; my fan stays in place so it maintains the 5mm distance). I did this because of something I had read / listened to talking about the efficiency of the fan being reduced and that even just a 5mm gap increases efficiency. I can't attest to these claims.