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Precision Twist CO500 12 Cobalt Steel Extension Drill Bit, Gold Oxide Finish, Round Shank, Spiral Flute, 135 Degree Point Angle

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Product Specifications
Cutting Direction
Finish Types
Gold Oxide
Drill Point
Material Type
Cobalt Steel
Cutting Angle
135  Degrees
Brand Name
Precision Twist
Flute Type
Shank Type

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Key Features

  • NAS 907 type J standards, for use in the aerospace industry
  • High-speed steel (HSS) containing cobalt is a good combination of toughness and hardness, for use on drilling into hard substances
  • 135-degree split-point angle, for self-centering, to reduce walking, for use with hard materials, and to reduce pressure on cutting edges
  • Gold oxide finish, to help retain cutting fluid and prevent chip to tool welding
  • Extra-length, for deeper holes and more reach than regular length

Product Description

The Precision Twist CO500-12 extra-length drill bit is made of high speed steel (HSS) and cobalt with a gold oxide finish that drills holes into a wide variety of metals and synthetic materials. It can drill to a depth up to four times the diameter of the drill size. The shank diameter is the same as the drill size.

The CO500 series has a type N flute form, with a regular helix (21- to 34-degree) angle, and performs best when drilling into alloy steel, nodular graphite, malleable cast iron, alloyed titanium, or alloyed nickel. The extra length and 135-degree split-point drill geometry provide extra reach and ensure a more accurate hole by reducing walking when the hole is started. The gold oxide is a low temperature heat treatment which reduces grinding stress within the tool, and has an appealing, easy-to-identify gold color. The finish retains lubricant to aid in wear resistance and chip flow. Gold oxide is commonly used to identify cobalt steel tools. Spiral flutes act as a passageway for chip extraction from the hole and for coolant to enter the hole. Right-hand twist brings chips up and away from the cutting edge. The extra length allows for more freedom in being able to drill a wider variety of materials.

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 can be used in hand-operated drills, standalone drill presses, or a lathe. They are made to ANSI and NAS 907 type J industry standards, which ensure that drill bits around the world conform to the same specifications.

Precision manufactures machine tools under the following brands: Precision Twist, Precision Dormer, and Union Butterfield. The company has locations around the world, and provides tools adhering to ANSI, NAS, and DIN standards.

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