Snap fit, supportless, 100% 3D printable.
I used tiny bolts and nut to secure the membrane, but give it a tap in the 3 holse with a hot soldering iron to fuse them together permanently, if you do not have bolts.
Membrane should be just 2 layers thick, cross line pattern.
Works pretty well. Blocks most air, and creates little but some resistance to the fan.
When outdoor is high pressure, it does rattle a litlle - at least with the filament and print thickness I used. You can sand lightly on the membrane to adjust resistance and to reduce rattle.
I scaled to 101% for a ultra tigh fit in the ventialtor.
Ventilator used: Sencys badkamerventilator Basic Ø125mm Timer CE
https://www.praxis.nl/verwarmingen-airco-s/mechanische-ventilatie-luchtafvoer/luchtafvoer/badkamerventilatoren/sencys-badkamerventilator-basic-125mm-timer-ce/5324271
| air_valve_membrane.stl | 34.1KB | |
| air_valve_one_way_ventilation.stl | 104.4KB |
