The Precision Twist 209CO taper-length drill bit is a 135-degree, notch-point, heavy duty, Morse taper shank drill bit made of high speed steel and cobalt with a gold oxide finish. Best performance with drilling into hardened, tempered alloy steel, nodular graphite malleable cast iron, and stainless. It is suitable for drilling to a depth up to four times the diameter of the drill.
The 209CO series has a type N flute form, with a regular helix angle (21 to 34 degrees). 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. 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 Morse taper is a shank that is tapered from one end to another. The taper of the tool fits into the taper of the tool-holder. The friction between the surfaces provides a secure holding systems and accurate placement of the tool. A drift pin is knocked into the slot at the tang to remove the tool.
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 DIN 1897 industry standards (metric sizing), which helps 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. They have locations around the world, and provide tools adhering to ANSI, NAS, and DIN standards.