To test the different types of tubing, I rounded up 2-foot lengths of 1 1/2-inch by 0.120-wall samples HREW mild steel, DOM 1020 mild steel, and 4130 chromoly. I also tested a piece of 6061 aluminum tubing of the same size as well as some chromoly with a thinner 0.065 wall thickness to see what it would withstand. The first test took place at a friend's shop that has a hydraulic tubing bender with a gauge that shows how much pressure is needed to bend the tube. We set each tube in the bender and tested them at exactly the same degree of a bend. We found the aluminum bent the easiest, with the HREW requiring about 25 percent more pressure. The DOM and 0.065-wall chromoly both required the same amount of pressure to bend, which was about 20 percent more than HREW, and the 0.120-wall chromoly needed 25 percent more than DOM, and 50 percent more than HREW.