Dust collector magnetic coupling

Magnetic couplings for 4" hose for woodworking.
You will need to purchase the magnets - 12mm diameter x 3mm thick, with hole for screw. (some get screwed into position, some get glued - for the polarity, or there is enough to screw them all into position and polarity lines up).
Magnet fixing hole is 3mm diameter, if your cutting your own "thread" pay attention to wall thickness.
I used 2mm wall thickness for strength, seems to be ok so far.
I have included the sketchup files in case you wish to make improvements, if you do please add a comment and link.
Possible improvements...

1. Strengthening web or thicker wall for the drum coupler, 3mm wall may not be enough if it gets banged by something (bound to happen).
2. Thread form for magnet fixings (4mm ?).
3. Increase segment count or apply smoothing to designs.
4. Slight recess or barbs, for flexible hose clamping. I am going end up using a jubilee clip, overlaid with pvc tape to protect from any "jaggy" bits.

Dust collector barrel is approx. 360mm diameter, the flange has been designed for this dimension.
Thin rubber gasket can be used between drum and flange, or silicone if you confident and super-careful about future damage(?).
Drum part has been fully populated with 8 magnets, but hose section can include the number of magnets you think are suitable, may not require the full 8 (?).

21/11/25 - This is a work in progress - other files yet to be finalised/published
edit 23/11/25 - Re-Upload of "coupling female for drum" - found one of the magnet recesses to be just shy of 3.2mm, magnet was sitting proud of surface.
edit 27/11/25 - Male part files added.