I considered building MOTHER’s tubing roller — used in building the framework for a backyard greenhouse — until I considered the safety of my fingers while using the roller.
So I built a much simpler tubing bender from a pallet and some scrap wood. It worked just as I hoped it would, and I had 20 hoops formed in 25 minutes. I just clamped one end of the tubing to the pallet and manually bent the tube around the arch. It was a whole lot safer, too!