An end mill is a type of milling cutter used to produce precise shapes and holes on a Milling or Turning machine. End mills are made of either cobalt steel (known as HSS or high-speed steel) or from tungsten carbide (known as carbide).
Carbide end mills are the most common because they are good for high production milling. Carbide end mills have the ability to operate at high SFPM and can run up to 2 1/2 times faster than HSS end mills. They are typically used on newer milling machines.
End mills are different than drill bits. An end mill is a rotating cutting bit used to remove material. While end mills are similar to drill bits, they are more versatile. End mills can usually cut in all directions. A drill bit can only cut along the axis.
It is important for machine operators to be familiar with the different types of milling cutters. Using the correct end mill is tantamount to a successful project. Carbide end mills are stronger than most others cutting tools.
Since carbide end mills are the most common milling cutters, they are available in a wide variety of lengths, diameters, and types.
Solid carbide end mills are significantly harder and more rigid than end mills made of other materials. However, carbide is brittle and tend to chip.
Like other carbide cutting tools, they are more expensive than cobalt tools.
The different shapes of the tip of an end mill are designed for a specific purpose. Some common shapes are ballnose, fishtail, v-carving, and straight. A ballnose shaped end mill will produce a rounded pass and is used in 3D contouring work. A fishtail cutter will produce a flat surface. V-bit cutters produce a “V” shaped pass and are perfect for engraving.