My Model A Ford has been sitting so long that the tires needed replacing. The problem is that if you work from the outside rim of the wheel, it scratches up the paint. I always work from the back side of the rim. Back when I used it for an everyday driver (1969-75) I kept destroying hub caps. They stay on the wheel, and got beat up when working the tires on and off.
I decided to make a fixture to hold the rim up off the floor. This does two things: saves the hubcap and keeps the rim supported while level. I determined that 3/4 EMT was a close match to the radius of the rim, so I rolled two rings, one for the rim and a larger one for a wider support base. I used scrap angle and square tube to connect everything, and sprayed Plasti-Dip on the rim support ring.
It works very well. The Plasti-Dip didn't hold up well, but the large contact area and smooth surface pretty much keeps the paint from damage. It makes it much easier to work the tires on and off, since the wheel doesn't flop around and pivot on the hubcap.