I like your enginuity and look forward to the video.
I, too, like to build vacuums sometimes. I have been known to take old vacuum motors and make vacuum cleaners of my own design with them. Incidentally, when I got the Hoover Fusion I mentioned earlier, I disassembled my worn out Hoover Dual V and took the motor out. I made the discovery that the suction motor could be wedges perfectly inside a two-liter soda bottle with the bottom cut off. I put the motor inside a cut up bottle, put the bottle inside a bucket, filled the bucket with old rags (sound insulation), and drilled holes in the bucket to diffuse the exhausted air after it blew through the old rags. What I describe doesn’t seem very elegant, but dare I say, it was. It was quiet and powerful! I stacked another 5-gallon bucket on top of the unit I just described to form the bag chamber. Inside would go a HEPA Kirby bag. This was my garage vac for a while.
I would also put together cyclonic systems periodically. I would use these cyclones in place of the bag. I would make cyclones out of anything I could get my hands on that was cone-shaped. One cyclone which I made out of a tapered thermos was particularly effective. I even cleaned my fireplace with it!
I have a spare used bin and cyclone assembly for my Dyson Cinetic upright. I have been throwing around the idea of attaching this thing to my shop vac and setting it up to run all day just sucking in air from outside. Where I live, the wind blows hard and frequently turns the sky brown with dust. I am curious to see how well the ultra-efficient Cinetic cyclones could purify this dusty air.
A cyclone system from a Dyson Cinetic might be a neat thing to try with your homemade vacuum.
Keep experimenting!