End mills are shank-type milling cutting tools used in a wide variety of industrial milling activities. A shank is the smooth part of cutting tools above the cutting edge.
End mills are not to be confused with drill bits, which are different cutting tools. Drill bits are cutting tools used to cut cylindrical holes. The differences between end mills and drill bits are in application, geometry, and manufacture.
A drill bit can only cut in the axial direction. However, end mills are cutting tools with cutting teeth at one end and on both sides. This feature enables end mills to cut in all directions, though some end mills cannot cut axially. Whatever cutting tools are required, whether they are end mills or drill bits, depends upon the work needed to be done.
All metalwork cutting tools have several things in common. They are tools used to remove metal from a work piece by shear deformation. Cutting tools need to be made out of a material that is harder than the material that is to be cut. Also, they must be able to withstand the heat generated by the metal cutting process. Their geometry needs to be specifically designed so that the cutting edge will contact the work piece without the rest of the tool dragging on its surface.
Several types of cutting tools include: broaches, reamers, tool bits, countersinks, counterbores, files, burrs, and slitting saws.
The materials cutting tools are made out of include: tool steel, high speed steel, tantalum carbide, titanium carbide, tungsten carbide, titanium nitride, ceramics, and more.
End mills were previously made from high-speed steel, but now are produced from mostly tungsten carbide. A carbide end mill is rigid and wear-resistant and is sometimes coated with chemical compositions to further reduce wear and friction.
There are several categories of end-and-face-milling cutting tools. A distinction can be made between center-cutting tools and non-center-cutting tools. Specifically, this distinction is whether or not the end mill can take plunging cuts. Additionally, the number of flutes, their helix angle, can also categorize end mills by the material they are made out of, and their coating material. Flutes, in the context of cutting tools, refers not to the musical instrument, but to a recessed part of the tool’s cross-section that keeps
chips away from the cutting edge as the tool rotates. End mills tend to have three or four cutting edges and flutes.
End mills can be further categorized by application. Among the multiple milling applications end mills are used for are: profile milling, tracer milling, face milling, plunging, and more. Another common use of end mills is in milling machine aluminum. When milling machine aluminum, a cutting tool with shallow flute depth and pre-dulled, polished cutting edges tend to get the best results.
