Selecting Tapered End Mill Bits on Amazon.com
End mills are rotary cutting tools with multiple edges for cutting and shaping the face and sides of a workpiece in machining applications. They provide a lateral cut, with the workpiece being advanced at an angle perpendicular to the axis of the tool. A tapered end mill is a center-cutting tool that can be used for plunging, and it is designed for side milling, contouring and machining angled slots. They are generally used in die-casts and molds.
Tapered end mills are available in a variety of taper angles, which are measured from the back of the flute to the tool's tip. They have straight, left-hand, or right-hand spiral flutes for varying applications, and they have either a square end or ball nose end. A square end cutter can mill square slots, pockets, and edges. The ball nose end will mill radiused slots or fillets and can be used for machining 3-dimensional contoured shapes.
Tapered end mills are typically made of high speed steel (HSS) or carbide for hardness and resistance to abrasion. They are often coated to increase hardness and cutting efficiency, usually with titanium nitride (TiN) or similar material. The number of flutes required will vary with workpiece material and generally determines the smoothness of the cut and the size of the chips ejected. End mills are produced in both imperial and metric diameters. They are sold in the traditional solid style and also as tool and insert combinations with replaceable cutting edges. General guidelines for choosing an end mill are available from most manufacturers and suppliers.