What Are the Different Types of Machine Tool Technology?

Before the different types of machine tool technology can be discussed, one must first know what a machine tool is. These tools are powered instruments that produce parts for other machines, usually machines used in manufacturing. Historically, machine tools have been powered by hand, water, and steam, but today they are most commonly powered by motors. Very simply, all machine tools operate by removing a portion of the material being worked on to produce the part desired. This removal consists of two parts, the cutting and the feed, and the “difference” in the different types of machine tool technology is the method that the machine tool uses to do this.

Milling is the first type of machine tool technology and it is similar in action to the milling of grain, which may be more familiar to most people. A wheel or circle with serrated cutting edges spins on a fixed axis and with a grinding action cuts away at the material being fed to it, in most cases metal. The different styles of milling depend on the orientation of the milling wheel to the surface being cut. When the “edges” of the wheel (parallel to the axis of rotation) do the machining, this is known as end milling. Face milling occurs when the “face” of the wheel (at a ninety degree angle to the axis of rotation) is what is cutting away at the material.

Turning can in some ways be considered the machine tool technology that is the opposite of milling. In turning, the material itself rotates rapidly on a fixed axis, and it is the generally more fixed cutting machine tool (known as the lathe) that is fed to the spinning object being worked upon. This usually happens to the outside surface of the part being made, and results in a rounded or cylindrical shape. When this occurs on an inside surface of the part, the technical term used to refer to this process is boring, and typically is used to make a hole or cavity larger and/or improve the precision of the part. If the lathe is set at an angle and fed along the side of the material, it produces an effect called threading, which creates the working parts of screws, bolts, and drills.

Drilling is the machine tool technology that initially creates the holes or cavities made bigger by boring. This technology is like milling in that the cutting surface is rotated rapidly, but it is generally fed to a fixed material. The part of a drill which does the cutting is known as the “bit,” while the shank provides the connection to the motor and holds the bit in place and against the cutting surface. A bit's cutting surface will have flutes threaded along the sides, with the cutting edges located along them. The flutes in this machine tool function by allowing waste material from the part being cut to exit, thus increasing efficiency.