It is the process by which a piece of steel or iron is heated to over 1000 degrees C and hammered into shape on an anvil. By heating, the steel becomes much softer allowing the blacksmith to shape and form it. The process is similar to molding play dough into shapes when you were a kid.
The steel does not become molten. The process of pouring molten steel into moulds is ‘casting iron’ which is done in a foundry and you end up with cast iron which can be poured into quite elaborate shapes but is quite brittle and does not have the strength of forged iron.
Iron is a pure element known on the periodic table as Fe. ‘Wrought iron’ is one of the earliest forms of useful iron. It was used for a lot until the industrial revolution took hold and steel-making took over. Wrought iron is almost pure iron making it relatively soft, it has varying percentages of slag (impurities) inclusions trapped inside it from the smelting process. You may be able to recognise wrought iron if you see old rusty piece of metal that looks like it has wood grain in it. This is caused by the slag seams inside the iron. These days wrought iron is generally only used for restoration and very specific purposes.
Steel is an alloy (mixture), made up of different elements the largest one being Iron (Fe). The most common steel used for decorative ironwork is ‘mild’ steel a relatively soft steel. There is a huge range of steels made with different alloying elements to achieve different properties. An example being stainless steel which has high percentages of nickel and chromium added to give it it’s high resistance to rust.
The finish on completed work varies from job to job and there are many different options available.
The most common ones are:
Blacksmiths use many and varied tools. One of the greatest things about being a blacksmith is that they can usually make any tools they need which comes in very handy.
The anvil is a large lump of steel used for hammering on. It has a point on one end called a horn used for bending on and a square and round hole at the other end for holding tooling and punching holes. This is one of the most necessary tools of a blacksmith and one of the few basic tools that cannot be easily made by the blacksmith.
Traditionally a blacksmith uses a forge to heat his work by burning coal, coke or charcoal. A forge has an air blast coming in from the back or bottom of the forge to intensify the heat of the fire. This was once done with a bellows made of wood or leather but these days it is much more efficient to use an electric blower.
Another common method of heating is a furnace burning usually LPG, propane, diesel or oil. This can be a very fast and efficient way of heating large pieces of steel.
Hammers are used for shaping the steel on the anvil. A blacksmith usually has a large range of different weights and shaped hammers for different types of work. A common weight for a forging hammer is 1 – 2 kg depending on the size of the work. A blacksmith often has someone helping them called a striker who uses a large sledge hammer weighting about 3 – 5kg.
Another common tool used these days is the power hammer which enables much larger work to be forged.
Tongs are used by the blacksmith to hold the hot work while forging it. They are made to fit all different sizes of bar. You need to make a specific pair of tongs for each different size bar you need to hold which means you end up with quite a of a lot of tongs, certainly not a bad thing. There are many special sorts of tong as well such as scrolling tongs for making bends on small material, typically the very centre of a scroll.
These are specific tools which are very varied where one half is made to fit into the square hole of the anvil and the top half has a handle (they are quite often mistaken for being a hammer of some sort) the top half is struck by the striker with the hot steel in between. Two of the most common types of top and bottom tools are ‘swages’ for making bar round in cross section and ‘fullers’ for putting groves in bar.
There are tools used just from the top as well like ‘hot sets’ used for cutting things, ‘flatters’ for smoothing out work and ‘set hammers’ for dressing up shoulders in work.
I hope this was helpful in explaining some of the very basics of the blacksmith process. If you are interested to learn more, there are many good books available on the internet and for hands on learning you could become a member of the NSW Artist Blacksmith Association which has get-togethers throughout the year and fosters learning.