The following three paragraphs are about the history of blacksmithing, general techniques, and hardening and tempering.
By Derice Hochstetler
In 1500 BC, the Hittites began smelting iron out of the earth, becoming the first known civilization in history to do so (Allen). Blacksmithing flourished from there. Then the Industrial Revolution hit. Blacksmithing all but disappeared (Allen). Almost all craftsmen of the ancient world were totally dependent on the blacksmith for their tools and other iron implements (Bealer). Since blacksmiths were dependent on no one in relation to their work, except the actual iron-maker, they were confident and independent men. Surprisingly, back then most blacksmith shops in any sizable town had from ten to fifteen apprentices and journeymen, who worked and learned from the master blacksmith (Bealer). After the industrial revolution, determined blacksmiths focused on more decorative items whereas olden blacksmiths forged more useful items (Allen). The Great Depression and WW II are what really almost brought blacksmithing to an end. It survived as forgotten art. Joyously, according to the Appalachian Blacksmiths Association, blacksmithing has made a comeback in the last forty years. The blacksmith today, however, is far different than the olden blacksmith, in that he uses modern tools and equipment to forge artistic work. Starting with the innovative Hittites, blacksmithing has made our modern civilization possible (Allen).
The blacksmith had many methods with which he fulfilled his important role in historic society. Forge welding was one of the hardest of the blacksmith’s techniques (McRaven). Starting by scarfing the metal, which is similar to beveling, the blacksmith then heated both ends to be joined up to blinding yellow-white heat, thus making the glimmering surface of the metal molten (Bealer). With sparks flying like miniature firecrackers, the blacksmith then hammered the two together, bonding the molecules of the two pieces into one piece (Allen). Back then, blacksmiths did not have unlimited choices of different sizes of metal stock, so they had to resolutely work with what they had (Bealer). Therefore, to make metal smaller they had to laboriously “draw” it out, which is hammering the metal in such a way that makes it smaller and longer. Fullering is making indentations in the metal which speeds this process up. To make a piece of metal larger or fatter, they had to “upset” it, which is making the metal push in on itself. “Punching” is making a hole in the red-hot metal with a punching tool. “Drifting” is widening a hole to the required size for the job intended (Bealer). Using a shear, hardie, or hot-cut chisel, the blacksmith can cut hot metal to the size required for any particular job (McRaven). Bending is simple to understand. Shrinking and riveting are alternate methods to welding for joining two pieces of metal (Bealer). Shrinking uses the rule that red-hot metal shrinks very slightly as it cools, while riveting is using a pin, upset on both ends, to hold two pieces together. For a decorative effect, blacksmiths can twist square stock using a vise and tongs (McRaven). Assuredly, among all these many methods, the most mysterious and glamorous is tempering the metal.
What does tempering really do? In relation to the mystifying properties of tempering, the olden blacksmith was credited with knowledge exceeding his skill (McRaven). Tempering a piece of metal, the composed blacksmith first quenches it, making it as hard and brittle as glass. He then slowly heats the metal to take as much hardness out of the metal as is desired for the tool in mind. It is technical, yet simple (McRaven). It takes a careful eye and, to be perfected, it takes experience (Bealer). Quenching temperature can be accurately determined by putting a magnet against the glowing and shimmering red-hot metal. When the metal becomes non-magnetic, it is the right temperature for quenching (Bealer). The three liquids most used for quenching are, pure water, salt water, and oil (McRaven). Curiously, the correct temperature for tempering can be shown by the colors that appear when the metal is heated. As the metal is heated, the first color that appears on the surface is a faint straw color, then bronze, purple, and blue. The straw color shows that the metal is only slightly softer then the hardened piece, bronze softer, and so on. The other factor that determines what color to heat the metal to is carbon content. Iron and mild steel cannot be hardened or tempered, because they have such low carbon content. Medium, high, and tool steel have progressively more carbon content in them, which makes them harder than iron or mild steel. So, to temper a knife of medium steel, it would need to be heated to a straw color along its edge, while a knife out of high steel would need to be a purple for the same degree of hardness (McRaven). Although tempering metal can be difficult, it is an important skill in blacksmithing.
Allen, David G. "Blacksmithing History 1." Blacksmithing History 1. N.p., n.d. Web. 17 Nov. 2016. <http://www.appaltree.net/aba/hist1.htm>.
Bealer, Alex W. The Art of Blacksmithing. New York: Castle, 2016. Print.
McRaven, Charles. The Blacksmith's Craft: A Primer of Tools and Methods. North Adams, MA: Storey Pub., 2005. Print.