Iron Design

A blacksmith is a person who creates objects from iron or steel by “forging” the metal; i.e., by using hand tools to hammer, bend, cut and otherwise shape it in its non-liquid form. Blacksmiths create such products as wrought iron gates, grills, railings, light fixtures, furniture, sculpture, tools, decorative and religious items, cooking utensils and weapons. A skilled blacksmith can make a good looking product that shows skill and ingenuity with the minimum amount of work and energy.

Blacksmithing

Blacksmiths work with “black” metals, especially iron. The black color comes from a layer of oxides that form on the surface of the metal during heating (called fire scale).

The term “smith” originates from the word “smite”, which means to hit. Thus, a blacksmith is a person who smites the black metals.

Blacksmiths work by heating pieces of wrought iron or steel in a forge until the metal becomes soft enough to be shaped with tools such as a hammer. Heating is accomplished by the use of a forge fueled by propane, natural gas, coal, charcoal, or coke.

The techniques of blacksmithing may be roughly divided into forging (sometimes called “sculpting”), welding, heat treating and finishing.

Forging

Forging is also referred to as sculpting because it is how the metal is shaped. Forging is different from machining in that material is not removed by these processes (with the exception of punching and cutting), rather the iron is hammered into shape.

There are five basic operations or techniques employed in forging: drawing, shrinking, bending, upsetting and punching.

These operations generally employ hammer and anvil at a minimum, but smiths will also make use of other tools and techniques to accommodate odd sized or repetitive jobs.

Drawing

Drawing lengthens the metal by reducing one or both of the other two dimensions. As the depth is reduced, the width narrowed, or both the piece is lengthened or “drawn out”.

Shrinking

Shrinking, while similar to upsetting, is essentially the opposite process as drawing. As the edge of a flat piece is curved such as in the making of a bowl shape, the edge will become wavy as the material bunches up in a shorter radius.

Bending

Bending at its simplest is simply that: bending the metal to a particular shape. Hooks are made this way, as well as loops and chain links from rod.

Bending can be done with the hammer and anvil although blacksmiths tend to make jigs and specialized tools to make the process easier and more consistent.

Upsetting

Upsetting is the process of thickening the metal by reducing one dimension and increasing the other two. It can be described as pushing the metal back into itself to thicken it.

Punching

Punching makes a depression or hole in the metal by driving a punch into or through the metal. Punching may be done to create a decorative pattern, or to make a hole.

Combining Processes

The five basic processes are often combined to produce and refine the shapes necessary for finished products. For example to fashion a cross peen hammer head a smith would start with a bar roughly the diameter of the hammer face, the handle hole would be punched and drifted, the head would be cut (punched, but with a wedge), the peen would be drawn to a wedge, and the face would be dressed by upsetting.

Welding

Welding is the joining of metal of the same or similar kind such that there is no joint or seam: the pieces to be welded become a single piece.

A modern blacksmith has a range of options and tools to accomplish this. The basic types of welding commonly employed in a modern shop include traditional forge welding as well as modern methods, including oxyacetylene and arc welding.

Heat treatment

Other than to increase its malleability, another reason for heating the metal is for heat treatment purposes. The metal can be hardened, tempered, normalized, annealed, case hardened, and subjected to other processes that change the crystalline structure of the steel to give it specific characteristics required for different uses. Only steel, not iron, can be heat treated, and generally speaking, the higher the carbon content of the steel, the more it can be hardened.

Finishing

Depending on the intended use of the piece a blacksmith may finish it in a number of ways:

• A simple jig that the smith might only use a few times in the shop it may get the minimum of finishing: a rap on the anvil to break off scale and a brushing with a wire brush.
• Files can be employed to bring a piece to final shape, remove burrs and sharp edges, and smooth the surface.
• The wire brush either as a hand tool or power tool can further smooth and brighten a surface.
  Grinding stones, abrasive paper, and emery wheels can further shape, smooth and polish the surface.
  There are a range of treatments and finishes to inhibit oxidation of the metal and enhance or change the appearance of the piece. An experienced smith selects the finish based on the metal and intended use of the item.
• Finishes include but are not limited to: paint, varnish, blueing, browning, oil, and wax.

The Blacksmith’s Tools

Small anvil

Over the centuries blacksmiths have taken no little pride in the fact that theirs is one of the few crafts that allows them to make the tools that are used for their craft. Time and tradition have provided some fairly standard basic tools which vary only in detail around the world.

“All a smith needs is something to heat the metal, something to hit the metal on and something to hit the metal with.”

The forge is the fireplace of a blacksmith’s shop. It provides the means to keep the fire contained and controlled.

The anvil at its simplest is a large block of iron or steel. Over time this has been refined to provide a rounded horn to facilitate drawing and bending, a face for drawing and upsetting and bending, and one or more holes to hold special tools (swages or hardies) and facilitate punching. Often the flat surface of an anvil will be hardened steel, and the body made from tougher iron.

Blacksmiths’ hammers tend to have one face and a peen. The peen is typically either a ball or a blunt wedge (cross or straight peen depending on the orientation of the wedge to the handle) and is used when drawing.

- excerpt from Wikipedia encyclopedia