Milling is a common machining process used in the manufacturing industry. It involves the use of a milling machine to remove material from a workpiece with a rotating cutting tool. Unlike lathes, milling machines don’t rotate the secured workpiece. Rather, they hold in the workpiece in place while exposing it to a rotating cutting tool. For a list of six essential milling-related terms and their respective definition, keep reading.
#1) Feed Rate
Also known simply as feed, feed rate is the speed at which a milling machine guides the workpiece against the rotating cutting tool. The higher the feed rate, the faster the workpiece is advanced. Although there are different metrics used for feed rate, most manufacturing companies measure feed rate in the length of the workpiece per revolution of the cutting tool.
#2) Face Milling
The term “face milling” refers to a milling process in which the corners of the cutting tool remove material from the workpiece. It’s used primarily to cut flat surfaces on workpieces. As the corners of the cutting tool rotate while pressed against the workpiece, it removes material from the workpiece’s surface.
#3) Peripheral Milling
In addition to face milling, there’s also peripheral milling. The term “peripheral milling” refers to a milling process in which the circumference of the cutting tool removes material from the workpiece. With the cutting action occurring along the circumference of the cutting tool, peripheral milling is highly effective at cutting deep slots or notches into workpieces.
An endmill is a special type of cutting tool used in milling processes that’s characterized by the ability to cut in all directions. It’s the most common type of milling cutting tool, as it supports face milling, peripheral milling, tracer milling and many other milling processes. While endmills look like regular drill bits, they feature a completely different design. Drill bits are only capable of cutting workpieces in an axial direction, whereas endmills can cut workpieces in all directions.
Like other machining processes, milling creates swarf as a byproduct. The term “swarf” refers to metal shavings or chips that are removed from machined workpieces. When a workpiece is milled, some of the material will be cut or scraped away. This excess material is known as swarf in the manufacturing industry.
#6) Bed Mill
A bed mill is another special type of milling machine. It’s characterized by the use of a spindle on an elevating pendent. To cut workpieces, the pendent moves the cutting tool up and down.