Very interesting design.
Due to practically every dust collector of any size being out of stock, I ordered a shop fox w1865 from amazon. It's an open box model so i got a good price but is essentially the harbor freight unit with the rikon impeller already installed, and with a better (but still deficient) filter bag.
I'm still sorting out my garage / wood working shop renovations but I'll start a scaled up version of these on the sidewinder tonight. Might be a while until i get to the actual assembly though.
I wonder what would be a good idea for clear tubing stock for the cyclone when scaled to larger sizes? I guess it doesnt have to be clear, but it is fun to watch, and it would help inform the iterative process.
It will be interesting to see the comparative differences in impact on realized CFM compared to a dust deputy style cyclone or a thien baffle. An inexpensive anemometer can be had from Amazon for under $20, and I'm sure it would be plenty accurate for those purposes.