If anyone is interested in making one of these, try to get some 19.5 or 22.5 rims from a trucking company. Most likely there will be sitting round. I work as a mechanic for a large fleet car hauler on average we find 2 rims a week cracked, we just toss the rims in our scrap pile, after we cut a gouge in them, so no one will try to re use them, Yes there are some stupid people out there!
You have inspired me to make on of these, my fire pit cage is burned out and this will do nicely.