A hex shank drill bit is a cutting device designed for use with a drill, drill press, or other rotating instrument. The shank of the drill bit is the part that is held by the tool; the hex shank drill bit will feature a shank with flat sides rather than a round profile. This design is useful for working with the jaws of a drill or drill press, and the bit will be far less likely to slip when cutting if a hex shank is used.
This design may also cut down on the cost of the drill bit, since less machining may be necessary. A hex shank drill bit can be made from bar stock, which means the flat sides already exist and will not need to be ground from a round bit. Some bits are, however, made from a round stock, and the shank is then flattened on several sides to create the hex shape. The hex shank is also convenient because the drill bit can then be used with certain types of screw type drivers; the six-sided hex head will fit into the driver snugly so the bit can be used by hand.
Another advantage to the hex shank drill bit is the higher torque application. A drill or press can turn the bit with more force because the risk of slippage is far lower. More force can be applied to the faces of the hex shank than it could otherwise be applied to a round shank, so hex bits can turn faster, cut faster, and remove materials more easily. Of course, these drill bit models cannot work with all types of drills or presses; some drills use a device known as a collet to hold the bit, and this design requires the use of a round shank that can be held tightly in the collet.
Like other types of drill bits, the hex shank drill bit may be sold individually in a particular size, though it is most likely to be sold as part of a set with several sizes included. Sets generally include the most commonly used sizes in either metric measurements or standard measurements. Larger kits may feature bits from both metric and standard sizes. Other kits may even include non-cutting bits, such as a hex shank bit with a Phillips-style head used to drive screws, or a grinding wheel attachment.