HIVE-L - Core One L Internal Carbon / Particulate Filter

HIVE-L Filter for the Prusa CORE One L

Why does this Exist?

HIVE-L brings my HIVE filter design to the larger Prusa CORE One L. It draws air from the print area through dual particulate filters and a multi-stage activated-carbon stack, then redistributes it near the bottom of the chamber.

The goal is to reduce airborne particles and VOCs while retaining chamber heat and encouraging more consistent temperatures throughout the enclosure. Especially useful when printing ABS, ASA, PC, PA, and other temperature-sensitive materials.

What’s Different?

• Redesigned to fit the CORE One L, making slightly more use of the space inside the side panel.

• Updated components based on lessons learned from the original HIVE.

• A beefier side handle to make handling the printer easier.

Otherwise, it uses the same filtration arrangement, hardware assortment, and print settings as the original. Matching updates for the CORE One version are coming soon!

Current Release Status

I wanted to get the design into your hands while I finish the supporting files. These items are coming SOON (as of 10/22/2026):

• A multi-piece, printable side panel. Only the steel side panel DXF is included right now, so this release currently requires a fabricated panel.

• Detailed photo instructions for both HIVE-L and the original HIVE!

The required print settings and a short assembly overview are below.

Features

• Dual robot vacuum–style particulate filters.

• Large, multi-stage activated-carbon canister.

• Dual 40 mm PWM fans: 4028 recommended, or 4020 with the included spacer.

• Curved ducting to redistribute filtered air within the chamber.

• Magnetically retained components.

• Uses the printer’s existing chamber filtration fan connection, with no firmware modification required.

Hardware Required

The hardware quantities are unchanged from the original HIVE.

• Prusa CORE One L

• 2× robot vacuum particulate filters

• Activated-carbon pellets

• 2× 40 mm, 4-wire PWM fans. 4028 recommended; 4020 supported with the spacer. Use 24 V fans, or 12 V fans with a buck converter.

• M3 Voron heat-set inserts

• M3×8 mm screws

• M3x12 mm screws

• M3×35 mm screws

• 6×3 mm magnets

• Buck converter, required for 12 V fans ONLY

• 4-pin JST-XH fan splitter, optional but highly recommended

• 4-wire Molex Clik-Mate jumper cable for the Buddy board connection

• ASA or ABS filament (PETG may be fine)

• Side panel fabricated from the included DXF; 1.5 mm steel recommended (aluminum MAY be fine)

Files Included

• Multi-piece and single-piece main body options.

• Carbon vessel, filter housing, grates, connectors, fan mounts, and side handle.

• Steel side panel DXF

Printing compatibility: All currently included printable parts fit on a CORE One or CORE One L except the single-piece main bodies. Those require roughly a 400 mm-class bed. Use the multi-piece versions for "smaller" printers.

Print Settings

ASA or ABS recommended throughout. PETG may work but remains untested for fitment and use.

Main Bodies

• 3 Perimeters / Walls

• 10% Support or Adaptive Cubic Infill

• 6 top / 4 bottom layers

• Brim recommended to help control warping

• NO Supports required

Filter Body Parts, Connectors & Fan Mounts

• 3 perimeters.

• 30% Adaptive Cubic Infill

• 5 top / 4 Bottom Layers

• Brim recommended

• NO Supports required

Filter Grates: Special Slicing Required

Preconfigured 3MFs are not included yet. Until those are available:

1. Use Split to Objects to separate each grate’s two overlapping components.

2. Set the grate to 0 top / 0 bottom layers, 2 perimeters, and 30% Triangles infill. These settings create the openings needed for airflow while retaining the carbon pellets.

3. Set the handle support component to 4 top / 3 bottom layers.

An expected G-code conflict warning will appear because these components overlap. The overlap can print rough, but the parts should still print successfully.

Assembly Overview

Detailed photo instructions are coming soon. For now, the basic sequence is:

1. Install the heat-set inserts and glue magnets into their pockets, checking polarity before gluing.

2. Assemble the multi-piece main body with its connectors and M3×8 mm screws, or use the single-piece body.

3. Mount both fans to the fan bracket, adding the spacer for 4020 fans, then attach the bracket to the body.

4. Assemble the carbon vessel, fill its stages with carbon pellets, secure the top flange, and install the particulate filters in their housing.

5. Remove the stock left side panel and retain its push pins. Fit the fabricated side panel and mount the HIVE-L assembly using the original pins.

6. Connect the fans to the printer’s chamber filtration fan port, using a buck converter for 12 V fans. Fit the carbon vessel, particulate filter housing, and honeycomb grille.

7. Add the following Start G-Code to your Filament Profiles that you wish to be filtered:
   
   ;HIVE enable

   M106 P4 S25

   ; This enables HIVE at approximately 10% fan speed ; Change S to adjust: 51=20%, 64=25%, 128=50% ; 153=60%, 191=75%, 255=100%

8. Add the following to your Printer End G-code to filter after every print AND shut down the fans, otherwise they may continue to run constantly after a print:
   
   ; HIVE post-print filtration

   M106 P4 S255 ; HIVE 100% (Reduce % if using Sanyo-Denki fans, 50% recommended, so S128

   G4 S240 ; Dwell (Wait) 120 seconds / 2 minutes

   M106 P4 S0 ; HIVE off

Notes & Limitations

• 4-wire PWM fans are required. Two- or three-wire fans would run continuously at full speed in this setup.

• Filtration performance has only been assessed by smell so far. Particle and VOC removal efficiency have not been measured, and reduced odor does not establish safe air quality.

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