PCHEPA Duo

Inspired by the Exhalaron clean air kit, but with an overall more integrated aesthetic, and at significantly lower unit cost.

What you'll need:

• a Nyemo TT-AP006 hepa replacement filter 2-pack
• a pair of 120mm PC fans, preferably quite and high static pressure, like Noctua NF-P12
• a PWM fan controller, like Noctua NA-FC1
• a 12v power source, like this USBC PD trigger
• misc parts like M3 heatset inserts, M3x35 flat head bolts, wiring for the fans/power, some sort of adhesive to mount the control module
• about 1.1kg of filament, 2-3 colors looks nice (vary base, cover, and maybe the mesh wall as a 3rd color)

For a detailed parts list and build guide see https://github.com/jcorbin/pchepa/blob/main/v1_build.md

All models are already oriented as intended to print.

General recommended slicer settings:

• layer height: 0.2
• 4 walls
• sparse infill: 15% tri-hexagon
• 4 top/bottom layers
• concentric top surface pattern
• no support material

The flexible mesh wall section should instead be printed with:

• 0 top/bottom layers
• sparse infill: 60% tri-hexagon
• infill direction: 90°

If you want to customize it for different filters, bigger fans, not to use heatset inserts, or want to follow along for future developments / variants, watch https://github.com/jcorbin/pchepa

Future versions will include:

• integrated battery bank
• other controller options, since the Noctua PWM controller is too expensive for what it is imo
• improved mesh wall integrity
• carrying options like loops for a carrying strap

Other variants that I'm planning:

• a 1 filter canister / "lantern" edition
• a 3 filter version to start scaling out towards that "luggable" space, while not quite yet going full CR box
• a version that integrate an even fancier control module with a builtin air quality sensor and display