Nuggets Inc - Air Filter - Hepa & Carbon

I have been looking for a good, cheap air filtration system and couldn’t find one that was inline and used cheap but reliable filters. So I built my own.
 

This is the “Basic 4-Slot Air Filter.” 

The print consists of a box and two cartridges that hold the charcoal and pre-filters. The HEPA filter needs to be purchased separately, but these are easily available and inexpensive. Simply buy a replacement filter meant for the Trotec Airgoclean 100E, and an In-Line Fan. The 3D-printed parts handles the rest.
 

The system is designed to filter everything from smoke to chemical fumes!

If you need a thicker carbon layer, you also have the option to chain multiple boxes together. Just print the thick-carbon version along with a multibox connector, if more filtration is required. 

THICK CARBON Version can be found - HERE

 

Bill of Materials (BOM)

1. Filtration Media (Required)

HEPA Filter

• Type: Replacement filter for Trotec Airgoclean 100E
• Efficiency: 99.97%
• Cost: approx. $10–20
• Link: https://de.trotec.com/shop/hepa-filter-99-97-fuer-airgoclean-100-e.html
• Hepa Filter Real Size: 294mm (h) x 212mm (w) x 22mm(d)

This HEPA filter is widely available, inexpensive, and intentionally used to avoid proprietary systems.

Pre-Filter Material

• Type: Woven fiber pre-filter mat
• Size (before cutting): approx. 240 × 240 × 20 mm
• Example link: https://www.amazon.de/dp/B0FRNNK43F

Any comparable pre-filter material can be used. Cut to size as needed. The pre-filter protects the HEPA and carbon from clogging prematurely.

Activated Carbon

• Type: Granulated activated carbon (coconut shell recommended)
• Quantity: ~1 kg / 2.2 lbs (per standard cartridge)
• Example link: https://www.amazon.de/dp/B098ZXF4BK

Used for smoke, VOCs, and chemical fumes. More carbon can be added by chaining multiple filter boxes together.

2. Hose Connectors (Required – choose one)

Exactly one of the following is required for proper operation:

• 100 mm direct hose connector (non-magnetic)
  For permanent or semi-permanent hose attachment
  Link
• 100 mm magnetic hose connector
  For quick-release hose attachment (recommended)
  Link

3. Optional Attachments

• Fume intake funnel
  For capturing solder fumes or 3D-printer bed emissions
  Link
• Multi-box connector
  Allows multiple filter boxes to be connected in series
  Link

4. Inline Fan (Required)

• Type: 100 mm inline centrifugal fan
• Recommendation: Hon & Guan or equivalent
• Selection criteria:
  • Prioritize airflow (CFM)
  • Avoid axial or PC-style fans
  • Inline duct fans only

Fan performance directly affects filtration efficiency. Undersized fans will reduce effectiveness, especially with thicker carbon layers.

5. Consumables

Sealing Material

• Self-adhesive foam tape
  • Width: 6 mm
  • Thickness: 1.5–2.0 mm
  • Use: sealing around the filter cartridge to prevent air bypass

6. Hardware

Threaded Inserts (Heat-Set)

• 22× M3 inserts – hose connector mounting
• 12× M3 inserts – filter cartridge mounting
• Size: 4.6 mm diameter × 5.7 mm length

Fasteners

• 20× M3 × 6 mm flat-head screws – hose connector
• 12× M3 × 6 mm flat-head screws – filter cartridge
• 2× M3 × 8 mm screws – upper hose connector
• 4× M3 × 16 mm screws – latches
• 8× M3 × 25 mm screws – latches
• 12× M3 hex nuts – latches

7. Recommended Filaments

TPU

• Use: gaskets and flexible seals
• Quantity: minimal

PETG

• Use: latches (more creep-resistant, less brittle than PLA)
• Quantity: minimal

PLA

• Use: enclosure and filter housing
• Quantity: ~1.5 kg