Milling equipment is used to fashion raw pieces of metal or other materials into useful parts or shapes. The different types of milling equipment are used to create different types of cuts; a metal lathe, for example, is used to create cylindrical or round parts, while a router is used to create edges on or holes into the metal. Machines known simply as milling machines can perform a variety of cuts, and they come in two general varieties: vertical mills and horizontal mills. To further distinguish between the many types of equipment available, machines may also be operated manually or using CNC controls.
CNC stands for computer numeric control, and most of the milling equipment in larger factories or industrial settings is likely to be CNC machines. The advantage of using such milling equipment is the ability to make the same cuts to the same tolerances over and over on different pieces of raw materials. Once the computer is set to make specific cuts, it can simply be reset when a new piece of material is placed on the cutting deck. Using a manually operated machine will require the machinist to measure and re-measure each piece of material to ensure the cut is uniform.
Vertical mills feature a rotating bit set above the deck or table of the machine. The raw materials to be milled are rested on the deck, and the bit will plunge downward to create a cut. Some machines feature a moving table that can be adjusted perpendicular to the angle of the bit. A horizontal machine features an arbor to which the bit is mounted, allowing for greater movement horizontally. The table on a horizontal machine may also be adjustable up and down, side to side, and at angles to allow for greater machining versatility.
CNC milling equipment is versatile but more expensive than manual machines; some CNC machines are even able to change bits automatically, meaning the machining time is cut down drastically. This is important for milling companies that need to produce as many finished pieces as possible in the least amount of time. Hobbyists and smaller milling outfits can save money by using manual machines, but the machining time is likely to be longer, meaning productivity will suffer. The accuracy of cuts can also suffer if several pieces of raw materials must be cut to the same tolerances. CNC machines ensure tight tolerances as long as the raw materials are set on the deck or table properly.
