In metalworking, milling has been the method of choice for many decades to produce geometric bodies from unmachined parts. For this purpose, the workpiece is clamped and machined with the required milling tools. Depending on the type of machine, this is done either horizontally – the spindle with the tool is approached from the side – or vertically. Here, the spindle comes from above. On machines with kinematics in the milling head, the tool can be approached to the workpiece in any angular position. Ultimately, the component decides which orientation is the better one. For example, chip fall is significantly better with horizontal milling, which is an advantage when machining bores.
As a rapid method of producing flat surfaces and notches, milling gradually replaced planing in the 19th century. The cutting manufacturing process is characterized by the fact that a milling tool with geometrically defined cutting edges is set in rotation in order to remove material from a workpiece. For this purpose, the tool is moved perpendicularly or obliquely to the axis of rotation in a feed motion. Unlike other metal-cutting manufacturing processes, milling cannot be done manually, giving it a very recent – but equally successful – history. In the 20th century, electric motors first became established as the drive for milling machines, followed later by electronic controls. Today, milling is considered one of the most versatile technologies in machining. The selection of machines is correspondingly wide.