Precision Twist R42C High Speed Steel Short Length Drill Bit, Black Oxide Finish, Round Shank, Spiral Flute, 135 Degree Point Angle, Z (Pack of 6)

The Precision Twist R42C stub-length, medium duty drill bit is a round shank bit made of HSS with a steam tempering finish. It is suitable for drilling to a depth up to two-and-a-half times the diameter of the drill. The shank diameter is the same as the drill size. For best performance, use for drilling into steel, free machining stainless steel, titanium, and unalloyed nickel. The R42C series was designed for the aircraft industry, but also works well for drilling into a variety of materials. The short length and 135-degree split-point drill geometry provide extra rigidity and ensure a more accurate hole by reducing walking when the hole is started. The finish retains lubricant to aid in wear resistance and chip flow. The Precision Twist R42C series has a type N flute form, with a regular helix angle of 21 to 34 degrees. The steam tempering finish gives a strongly adhering blue oxide surface that acts to retain cutting fluid and prevent chip to tool welding, reducing the formation of a built-up edge. Spiral flutes act as a passageway for chip extraction from the hole and for coolant to enter the hole. 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. These drill bits have a right-hand twist that brings chips up and away from the cutting edge. They are made to ANSI (fractional sizing) and NAS 907 type C industry standards, which help ensure that drill bits around the world conform to the same specifications. Dormer Pramet manufactures cutting tools under the following brands: Precision Twist Drill, Dormer, Union Butterfield and Pramet. The company has locations around the world, and provides tools adhering to ANSI, NAS, and DIN standards.

• NAS 907 type C standards, for use in the aerospace industry
• Short-length, for better rigidity and increased strength
• 135-degree split-point angles are self-centering, reduce walking, for use with hard materials, and reduce pressure on cutting edges
• Steam tempering (also called black oxide) finish, to retain cutting fluids and to prevent chip-to-tool welding
• High-speed steel (HSS), for use on a wide variety of materials