Exhaust check valve for K40 Laser

Update as of February6, 2022:
Added a protection ring to keep the axle in place and to prevent flap from touching the exhaust tube. Flapdesign adjusted for clearance. See last picture.

This is a simple to print and assemble check valve preventing cold air getting into the room, where the K40 is located.
Use a piece of welding rod or filament as an axle. Fix the axle to the flap with superglue if needed. Cut the axle a bit shorther than flush to prevent binding on the exhausttube. New: Use the protection ring if applicable to keep axle in place and protect flap from exhausttube..

You might need to add a bit of maskingtape around the tube for an airtight fit to the K40.

Here it is in action:
https://youtu.be/11aAburDRqo

This is only tested with the new type of K40 with an integrated exhaust 24V fan.
OpenSCAD file is included as usual for easy adjusting.

Have fun!

Cheers
Armin