After using the typical pile of wagon and car rims and pipe cuttings to bend cold roll rod rings, I came up with this more graduated contraption. The first two I built where shorter and fatter, and sat on a 55 gallon drum. You could stand in place, place the lead of your rod into it, and with gloved hand holding rod, spin the cone on the drum creating rings out of any length of rod. Hold the rod firmly against the unit or your rod will spring out prematurely! It looked like a NASA Gemini Capsule. This particular one looks like a Christmas tree (not made by me) and you walk the rod around it to make your rings. Stand clear! Here the tire holds it from spinning on the ground. Notice in the close-up that all the ring welds are on the top side. That's because as you insert and bend the rod against the bottom side of the chosen ring you need a snug purchase all the way around. This design is great for short runs of many different diameter rings. You can even bend 3/8" cold roll but it's hard on the bender. Several of these have been in service since I built the first two in the mid seventies. The first one took about a day to construct using pipes and rims to produce the initial rings.Other tools used were bolt cutters, an arc welder, and #6011 electrode. Simple stuff. Ted Baumgart