Drill bit shank The name comes from the German "Stecken – Drehen – Sichern" (Insert – Twist – Secure). In German-speaking countries the back-formation "Spannen durch System" (Clamping System) is used, though Bosch uses "Special Direct System" for international purposes. The triangle shank is almost always made by machining three flats on round bar stock. It is intended as a minor modification of a straight shank, still allowing it to be held in a 3-jaw drill chuck, but allowing higher torque transmission and limited slipping. The Morse taper twist drill bits pictured right are used in metalworking. The full range of tapers is
Drill bit gimlet bit cuts the side of the hole. The hinge sinker bit is an example of a custom drill bit design for a specific application. Many European kitchen cabinets are made from particle board or medium-density fiberboard (MDF) with a laminated melamine resin veneer. Those types of pressed wood boards are not very strong, and the screws of butt hinges tend to pull out. A specialist hinge has been developed which uses the walls of a diameter hole, bored in the particle board, for support. This is a very common and relatively successful construction method. A Forstner bit could bore