Normally made of high-speed steel, milling cutters are the interchangeable blades of a milling machine. Milling is defined as, "the process of machining flat, curved, or irregular surfaces by feeding the workpiece against a rotating cutter containing a number of cutting edges," according to Metal Web News. The teeth provide fast and efficient cutting. There are 13 different types of milling cutters, available in many widths, angles and diameters.
End mills are one of the 13 different types of milling cutters, and the most commonly used. End mills are generally used in a vertical milling machine. The teeth are powerful enough to drill their own starting holes. End milling cutters stay true to their name, with teeth on the end, and generally along one side.
Similar to an end mill, a slot drill is used when an end mill cannot complete the job. They are distinguished by two fluted cutters and a single tooth. Slot drills are used for cutting keyway slots. Cutting directly into the material, a slot drill uses its teeth to break through work material.
Roughing End Mill
You would use a roughing end mill if you needed to cut out large chunks in wavy patterns. A roughing end milling cutter leaves a rough surface behind. Also referred to as ripping cutters, a roughing end mill is recognised by its wavy teeth. Roughing end mills are known for quieter cutting, as their wavy teeth minimise vibrations.
Involute Gear Cutter
Involute gear cutters are available in eight different sizes. These milling cutters come in circular form. They are distinguished by 12 cutting teeth organised around its circumference.As with all milling cutters, there are a variety of diameters to choose, making involute gear cutters a very versatile cutting tool.
Slab mills create wide cuts. The cylindrical shape cuts horizontal surfaces. Made from high-speed steel, the teeth of a slab mill are at a helix angle. The helix angle allows the teeth to engage slowly, distributing force. Slab mills cut on a periphery and are used on horizontal milling machines.