That impeller got me thinking about something else......
I built a set of balancing ways to make it. If you are making any machinery with spinning parts, like an impeller or sanding drum, it's not enough to make it round or cylindrical., it need to be balanced.
I made this set out of scrap plywood and 2 Starret 6" rules for the contact surface.
I also modified it to use for building and truing bike wheels, but can convert it back for balancing.