Machining involves removing material from metal to achieve the desired final shape, size, and finish and is one of the most effective ways of creating detailed objects. The machining process can be categorized as follows:
- Drilling – The process of making or enlarging a hole using a rotary cutting tool (typically a multipoint tool). The drill bit is vertically rotated into the work piece at high speeds cutting away chips from the material. The chips then exit the hole through “flute” (grooves) in the drill bit.
- Turning – The workpiece is attached to a fixture which is secured to a lathe. The work is rotated while the cutting tool (typically a single point tool) remains stationary. Material is chipped away as the work rotates creating the desired shape.
- Milling – The workpiece is attached to the fixture which is secured inside the milling machine. The cutter (typically a multipoint rotary tool) rotates at high speeds cutting away material from the piece. Unlike the drilling process, milling machines offer the ability to move the work as it’s cut to create holes of different shapes.
- Grinding –Material is removed from a workpiece using a rotating abrasive wheel. While the grinding wheel (or, in some processes, the work) is rotated at very high speeds, the abrasive grains on the wheel remove tiny chips from the work resulting in the desired shape and finish.
This technique can be time consuming, but may be used to create many products of different dimensions with intricate patterns. In addition machining produces a great surface, and can be cost effective for products needed in small quantities.