Most steel bars are either hot-rolled or cold-rolled; a cold rolled bar is shinier than a hot rolled bar, but is also harder to bend. Stainless steel is even harder to bend. The stronger the steel, the more the bend will approximate a "V", while the weaker the steel, the more the bend will look like a "U." Most strongmen who bend steel bars prefer to work with lengths of five to seven inches (12.5 to 17.5 cm). (A common strongman feat was bending a 60-penny nail, which is 6 inches [15 cm] long.) The shorter the bar, the harder it is to bend, as shorter lengths give less bending leverage than longer lengths; however, some prefer a six inch (15 cm) bar to a seven inch (17.5 cm) bar because of the way the stock was formed. You can buy steel bars in the optimal length for hand-bending from some online retailers or buy longer bars either online or from your local hardware store and cut off a piece of the desired length. To cut the steel bar, use a pair of bolt cutters, preferably about 24 inches (60 cm) long. Wear safety goggles when cutting, as short pieces can travel at high speed when cut from the larger bar stock. Grind or file off the cut end to smooth it. Thicker bars are harder to bend than thinner bars. Doubling the diameter quadruples the amount of force required to bend the bar; it takes four times the torque to bend a 3/8-inch (9.6 mm) bar as it does a 3/16-inch (4.8 mm) bar.
Choose the right steel alloy. Choose a comfortable length of steel bar. Choose a comfortable thickness.