Mild Steel Bar Stock Forged from an Ingot

Mills roll steel ingots into bar between grooved rolls. Before rolling mills, and in any forge today, the same shapes are drawn out by hand: cut a billet from a low-carbon (mild) steel ingot, heat it, and hammer it longer and thinner, square first; then eight-sided and round in a swage block for round bar and rod, or flattened for flat bar. Hand-forged bar is not as exact as rolled bar: measure it and allow for that. Mild steel does not harden when cooled in air, so the bar is left to cool on its own.