Conditions of use of end mill

Number of blades

This is one of the more critical factors that determine an end mill’s performance. If the number of blades on an end mill is small, it would result in a small cross-sectional area and, thus, reduce stiffness, which may cause bending during cutting, but on the other hand there is a large space for discharge of chips, which makes the discharge convenient. If the number of blades is large, the chip pocket becomes small to allow a reduced capacity for chip storage but, conversely, its cross-sectional area as well as stiffness increase.