Metal Machining and Fabrication

Metal machining and fabrication are manufacturing processes that use cutting tools to shape a metal part by removing material until the desired dimensions and form are achieved. Unlike casting or forging, which create the part's shape in a single operation, machining is a subtractive process that allows for exceptional precision and detail. 

The two most common machining processes are turning and milling, which complement each other to create a wide variety of parts.

• Turning: This process is performed on a machine called a lathe. The workpiece (generally cylindrical) rotates at high speed, while a stationary cutting tool moves along its surface, removing material and creating diameters, cones, grooves, or threads. Turning is fundamental for manufacturing components with circular symmetry, such as shafts, bolts, and pins.

• Milling: In milling, a rotating cutting tool (milling cutter) moves over a stationary workpiece to remove material. Unlike turning, milling is used to create flat surfaces, grooves, cavities, and complex shapes. The CNC (Computer Numerical Control) milling machine is a modern tool that automates this process and achieves astonishing precision.

For parts requiring extremely tight tolerances, high-precision machining processes are used:

• Grinding: This uses an abrasive wheel that rotates at high speed to remove small amounts of material from the part's surface. Grinding is used to achieve a very fine surface finish and very precise dimensions on hard materials, such as hardened steels.

• Electrical Discharge Machining (EDM): This method uses controlled electrical discharges to erode material. An electrode and the workpiece are submerged in a dielectric fluid, and the electrical discharge creates a plasma channel that vaporizes the metal. EDM is ideal for cutting complex shapes and tiny holes in very hard metals that would be difficult to machine with traditional cutting tools.

Machining and fabrication are indispensable processes in manufacturing, enabling the mass production of identical components and the creation of unique parts for the automotive, aerospace, medical, and technology industries.