How does a milling machine cut metal?

A milling machine cuts metal by feeding a workpiece against a rotating cutting tool known as a milling cutter. Unlike single-point tools, these are multiple-point cutting tools that feature two or more cutting edges.31

The cutting process can be categorized by the direction of the tool's motion relative to the workpiece:

• Upcut (Conventional) Milling: The cutting motion of the tool is directed against the feeding direction of the work.2
• Climb (Down) Milling: The cutting motion of the tool occurs in the same direction as the feed of the workpiece.2

To ensure effective cutting and prevent the tool surface from rubbing against the metal, relief or clearance angles are incorporated into the design. Additionally, rake angles are often used to facilitate a wedging action that forms chips while reducing friction and heat during the operation. These machines are capable of producing a wide range of shapes, including flat surfaces, grooves, inclined surfaces, and gear teeth.13