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7 MILLING AND MILLING CUTTERS DEFINEDMotions in MillingIn milling, the primary motion is the rotary motion of a milling cutter, while the feed motion is the translational motion of a machined workpiece relative to the cutter. Depending on the type of milling machine, there are several ways to facilitate feed motion. Table FeedTraditionally, feed motion in milling was achieved by moving a machine table that held a machined workpiece. Consequently, the speed of the feed motion, known as the feed speed, was closely tied to the velocity of the moving table, commonly referred to as %u201ctable feed.%u201dThe most common approach involves moving the workpiece while the rotating milling cutter remains in the same position. Another technique is observed when the workpiece is stationary, and the rotating cutter moves translationally. Lastly, in the third approach, both the rotating milling cutter and workpiece are moved relative to each other.vfnFig. 1. Example of motions in milling: primary motion is the rotation of a milling cutter with rotational velocity n, while feed motion involves the rectilinear movement of a machine table carrying a workpiece mounted on it, with a linear speed vf.Milling Methods andMilling OperationsThe cutting edges of a milling cutter are located on the cutter periphery, cutter face, or both. Therefore, depending on the area of the cutter involved in the cutting action, there are several milling methods: peripheral milling, face milling, or a combination of both.In peripheral milling, only the teeth on the outer periphery of the mill are engaged in cutting (Fig. 2). Peripheral milling is commonly known as %u2018slab milling%u2019, and the corresponding mill is referred to as a %u201ccylindrical mill%u201d, %u201cslab mill%u201d, or even %u201cplain mill%u201d.VfnFig. 2. Peripheral (slab) milling.