HAFC V2 - Hackman Automatic Filament Cutter V2

HAFC V2 – Hackman Automatic Filament Cutter

by Hackman3D

Here's a link to get the necessary hardware. No partnership or affiliation involved, but since the price is reasonable, I haven't asked for a commission.

HAFC Aliexpress Pack back in stock :

https://a.aliexpress.com/_EH25h7a

Video in use, sorry it's on a Bambu printer, I work on an holder for my prusa mini

https://www.youtube.com/shorts/-0ykCtMGRbw?feature=share

🧠 Concept & Purpose

The HAFC V2 (Hackman Automatic Filament Cutter) is a fully mechanical system compatible with any FDM 3D printer using 1.75 mm filament with a PTFE tube.

I designed it to solve a very common issue:

filament getting stuck on the spool (tangles, friction, jammed spool…).

Instead of forcing the extruder:

•filament tension increases

•the mechanism triggers

•the filament is cleanly cut

•the printer pauses thanks to its filament runout sensor

👉 You just reload filament and resume the print

No electronics, no sensors involved —

everything is passive, simple, and reliable.

⸻

⚙ What’s new in V2

This version is based directly on feedback from V1.

The main focus was improving reliability and behavior:

•more compact design

•faster to print

•improved tolerances (filament path + internal sliding)

•added return spring → automatic reset

•stronger resistance to reduce false triggers

•improved magnet alignment

•possibility to add extra magnets externally to fine-tune trigger force

The result is a more stable and predictable system, even on very precise machines.

⸻

⚙ How it works

The filament goes through the HAFC using a PTFE tube and Pneufit connectors.

If the spool gets stuck:

•tension increases

•the sliding module moves

•the blade cuts the filament

➡ The printer detects filament runout and pauses automatically

Magnets control the trigger force,