Prometheus’s Gift of Fire Led to Forge Welding
A common site in most manufacturing facilities and home workshops is the arc associated with welding.
Although ubiquitous in the modern world, the welding process has evolved over thousands of years. Until a couple of hundred years ago, forge welding was the only way of connecting different pieces of metal.
What is forge welding and its story? Continue reading.
Forging Metal
Forge welding requires heat. How mankind developed the method of creating heat using fire has two origins.
Prometheus
After being tricked by Prometheus, the Greek god, Zeus, punished man by taking fire away. Fortunately for us, Prometheus called the benefactor of man, wasn’t going to let mankind suffer from his trickery. He traveled to the gods’ workshops and from Hephaestus, took a fennel stalk containing the fire.
Prometheus returned to earth and showed mankind how to make and use fire. With this knowledge, mankind will never again be without fire. For this and previous acts against him, Zeus chained and sent an eagle to eat Prometheus’s liver. Unfortunately for him, the liver re-grew each night while the eagle returned each day, eating the organ again.
Nature
The pantheon of Greek gods and their mythology makes for compelling reading. The most likely source of the fire was nature in the forms of lightning strikes and volcanoes. People used myths to explain why fire became such a powerfully destructive force.
Fire became mankind’s tool for cooking, heat, and protection. Eventually, fire became the impetus for other purposes.
Early Metalwork
There are two aspects of forge welding: fire and metal. Telling this story needs context from both aspects. There needs to be metal for forge welding to work!
Bronze Age
The Bronze Age began between 3300 to 2100 BC. The earliest bronze artifacts derived from hot forging came from the Iranian Plateau between 5000 to 4001 BC. Archeologists determined the oldest tin alloy bronze work occurred around 4500 BC in Serbia.
In other words, bronze has been around for a long time.
Interesting facts regarding bronze:
Iron Age
The Iron Age began around 1300 to 1200 BC as iron became cheaper than bronze.
The evolution from the Bronze Age to the Iron Age resulted in the ability to improve iron. It’s thought that creating carbon steel was an accidental discovery around 1000 BC from combining molten iron and charcoal from the smelting fire.Meteorites were likely the first iron source, although it’s hard tracing iron’s history because quickly iron rusts. Among the earliest known meteorite artifacts are Egyptian graves containing iron beads around 7000 years ago.
Two interesting facts regarding iron:
The Metal Forge
The generic term forging defines all the ways of using heat and pressure for the metalwork process. Metal forming is among the oldest working techniques used by mankind. It was the way of creating weapons, shipbuilding, and farming tools.
Basically, it’s where heat is generated, usually using coal or gas as the heat source, and then the metals are joined using pressure (hammering) to bind the metals together. Forging is also known as blacksmithing…
The primary tool used in forging metal is a stationary or portable forge. There are four main components of a forge:
- Hearth: location of generated heat
- Blower: oxygen source for increasing heat
- Tuyere: path the oxygen follows accessing the fire source
- Water Basin: for cooling the metal
The Forging Process
There are two types of forges:
- Updraft: fumes and smoke produced during the forging process pushed through an overhead hood unit
- Downdraft: fumes and smoke produced during the forging process pushed through down through a series of ducts.
Of the two forging unit types, the downdraft version provides better ventilation and air circulation.
The forging process is straightforward. Using a cast-iron forge, an air blast adjusts the fire’s heat to the raw metal to the correct temperature forging it into various shapes. The image below illustrates the basic forge layout.
Anvil
An anvil is a primary tool used in forge welding. Primitive versions of an anvil were rock.
Original anvils were stone or rock slab. Over time, anvils were made of bronze, iron, and eventually steel. Although anvils are anathema to Wile. E. Coyote, especially the ACME brand, they’re a vital tool for metalworkers and necessary for achieving a proper forge weld.
As the need for tools and implements changed over the years, so did the anvil’s shape. Its shape worked through many incarnations until the 1800s when the London Pattern became common.
There are five essential components of anvils:
Horn
The horn is the curved piece at the front of the anvil. The blacksmith uses the horn for hammering different curves into the metal piece they’re forging. Some anvils have more than one horn varying in shape and size.
Step
The step is next to the horn and below the anvil’s face, generally used as the cutting area. This edge step cuts the metal as the smith hammers at the same time. If used consistently, frequent cutting on the edge damages the step.
Face
The main slab where most of the hammering takes place is the face. The edges around the face are curved, preventing cutting the metal while it’s hammered on. The face connects the step and horn.
Hardy Hole
The square-shaped hole through the anvil is called the hardy hole. If needed, tools are attached to the anvil using the hardy hole. The spot is also used for bending metal and hole punching.
Pritchel Hole
The pritchel hole functions the same as the hardy hole except it’s rounded, not square.
Changing Times
Forge welding was the only method of welding pieces of metal together for thousands of years. In the 1800s, however, times and practices changed. As outlined in the first article of this series, the advent of acetylene welding represented a sea-change for manufacturing. Industrial welders were no longer anchored to one spot; compressed gas containers’ portability allowed them freedom for doing the work on job sites.
In Sum
Forge welding was the only welding game in town for several millennia until the 1800s. As modern welding methods slowly became standard, forge welding drifted to the background. Welding using the forge, however, now exists as a blacksmith’s craft. The best mainstream example of its craftsmanship is History Channel’s Forged in Fire TV series.
Prometheus’s sacrifice gave mankind the gift of warmth and hot food and the ability to improve our quality of life. Although consigned to predominately hobbyists, the sound of hammering on anvils won’t fade away anytime soon.
Originally published at https://www.schuettemetals.com on September 10, 2020.
