Re: Making the "Hoop"
Theres lots you can do to bend these. the trick is to make sure the sides are held tight to give you something solid to bend against and keep the pipe from kinking.
Ive used a bunch of hard wood boards laminated together then cut into a disc with the pipe diameter cut into the outside circumference. then bent the pipe around it with a lot of leverage.
You could even use a rubber hose of the same diameter to leave an imprint in cement to bend the pipe around. That works really well if you have one of those harbour freight pipe benders. Use the largest radius mandrel and fill it with cement to make it work with a small pipe with larger radius.