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 variety of cutter designs, but some are still produced with the original version. The gimlet bit is intended to be used in a hand brace for drilling into wood. It is the usual style of bit for use in a brace for holes below about diameter. The tip of the gimlet bit acts as a tapered screw, to draw the bit into the wood and to begin forcing aside the wood fibers, without necessarily cutting them. The cutting action occurs at the side of the broadest part of the cutter. Most drill bits cut the base of the hole. The