Upgrading from V2 of my fume extractor (based on a salvaged brushed DC portable vacuum blower motor), as higher airflow and lower noise was necessary, as well as wanting a better filter system.
I purchased a generic Xiaomi replacement air filter with carbon-filter insert, and designed around that.
The 3D printed assembly is in 3 pieces: a flange that holds the ducted fan and covers the air filter inlet, a connector that covers the flange and provides connection to a previously-designed twist-lock connector, and a large clip that securely holds the assembly to the air filter by clipping over the rim.
Closeup of assembly minus flexible tube
