CNC milling machines use clamps to hold a workpiece--the block of metal or other material to be shaped--in place while a spinning blade or drill bit cuts and shapes it. The blades usually move on a minimum of three axes, but can use up to six. Milling machines can be used for a variety of applications and are one of the most common types of CNC tools.
While the cutting tool rotates at high speed, similar to a drill, and removes material. Mill cutters can have many blades on one cutter, in contrast to a lathe that only uses a single blade. For reference, a standard drill bit typically has one or two blades, but a mill cutter can have two, four or more. Some mills even have multiple cutters on one machine to make cutting jobs go quickly.