High Speed Steel (HSS) tools such as drills, taps and reamers are commonly used on CNC machining centers for hole making operations.
Twist Drills
Twist drills have a conical cutting point at the tip of a cylindrical shaft that has one or more helical flutes. The flutes are designed to evacuate chips out of the hole being drilled. Twist drills are available in a variety of sizes, lengths, materials and coatings, but the most common are High Speed Steel (HSS) and solid carbide.
Drilling tools are end-cutting tools designed for producing holes in a workpiece. The shank of a drilling tool incorporates flutes, or grooves, that allow for the entrance of fluids, along with ejecting the cut ships from the workpiece.