What is Metal Machining?
Machining is a manufacturing process in which material, often metal, is cut to a desired final shape and size by a controlled removal process. Material removal processes like machining are often referred to as subtractive manufacturing — in contrast to additive manufacturing (3D printing), which uses controlled addition of material.
Machining is a part of the manufacture of many metal and plastic products, but it can also be used on other materials such as wood, ceramic, and composites. Modern machining is carried out by numerical control (CNC), in which computers guide the movement and operation of mills, lathes, and other cutting machines.
How Does Metal Machining Work?
The three principal machining processes are:
1. Milling operations use a rotating cutting tool to bring cutting edges to bear against the work material. Milling machines, or simply mills, are the principal machine tool used in milling operations.
2. Turning operations rotate the work material as the primary method of moving metal against the cutting tool. Lathes are the principal machine tool used in turning.
3. Drilling operations produce or refine holes by bringing a rotating cutter with cutting edges at the lower extremity into contact with the work material. Drilling operations are mostly performed in drill presses, but also on lathes and mills.
Other miscellaneous operations include shaping, planing, boring, broaching, and sawing.
Unfinished work material requiring machining needs material removed to create a finished product. A finished product would be a workpiece that meets the specifications set out for that workpiece by engineering drawings or blueprints. Examples of more advanced shaping techniques include:
Computer numerical control (CNC) machining
Electrical discharge machining (EDM)
Electro-chemical machining (ECM)
Advantages of Metal Machining
As a process for manufacturing metal parts, machining offers several advantages:
"Lights out" process reliability
Low labor requirements
Smooth surface finish
Diverse material selection