Hole Enlarging Drill BitsFlute Length: 40mmOverall Length: 80mmSolid carbide tools offer long tool life and faster cutting speeds than other substrates, but are more brittle and must be used with rigid toolholding systems. Suitable for carbon steel, chilled cast iron, ductile iron, gray cast iron, die steel, heat alloy steel, tool steel. Uncoated tools feature just the base substrate without any additional treatment or coatings and are suitable for a wide range of applications. Round shanks allow use with a wide variety of toolholding systems. When run in a counterclockwise direction (right-hand cut) spiral fluted tools evacuate chips up and out of the cut to reduce clogging.Drilling, or hole making, is the most common metalworking operation in the world. Twist drill bits are the most common type of drill bit used. Twist drill bits are commonly used to drill holes with hand-operated drills, standalone drill presses, or lathes. The flutes of the drill bit act a passageway for chip extraction from the hole and for coolant to enter the hole.