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Metalworking is the craft and practice of working with metals to create parts or structures. The term covers a wide range of work from large ships, bridges and oil refineries to delicate jewellery.

It includes a wide range of skills and the use of many different types of tools. From early beginnings of civilisation, metalworking has developed using different metals and alloys, increasing use of power sources, mechanisation and automation.

Metalworking includes the following processes.

Hand tools
Hand tools were the original way of manipulating metal, and remain important today. They have been replaced by mechanisation in Manufacturing and Power tools for people using them as a hobby or trade. An early trade was that of the Smith using a forge.

Machine tools
Early mechanisation replaced human or animal power with water driven versions, then replaced by steam power and later electric motors. More power meant bigger machine tools and more productivity. With standardisation and improved quality came Mass production.

Sheet metal tools
The flexibility provided by thin sheet metals when used in fabrication lead to the use of guillotines, bending presses and punches. Modern methods produce complex shapes like those in car panels that are bent to shape and include multiple holes.

Welding and Joining
The joining of metals is done through brazing, soldering, welding and recently gluing. This allows complex or large shapes to be made from smaller pieces.

Casting
There are many forms of creating a pre-shaped part through casting, moulding, sintering, etc. This part may then be finished using machining methods or used in other structures. Modern methods are so accurate that the complete finished part can be created using these methods.

NC and CNC machines
A number of methods have been developed to control machine tools. Numerical Control (NC) is generally achieved through hardware, which provides a good level of repeatability at a cost of an increased set up time. If those hardware controls are replaced by software, and accurate positioning control, the set up is reduced and flexibility increased. The machine then becomes a Computer(ised) Numeric(al) Control(led) (CNC) machine.

Robots and automated machining lines
When the machining process can be controlled automatically it is beneficial to use automated methods to load and unload machines, and to transfer the workpieces between machines. This lead to the use of robots and transfer devices. Robots are also used where the machining process requires a large flexibility in the positioning of the machining head.

See also Metallurgy for the structure of metals and alloys.