Precision Twist Drill 5998768 Letter I Hss Drill Bit

Product Description

The PRECISION TWIST DRILL 5998768 is a jobber length drill bit sized to Letter I, with a decimal equivalent of 0.272 inches. Ground from high speed steel with a steam oxide coating, it runs a 135-degree split point for faster penetration and reduced walking on entry. The two-flute spiral design clears chips efficiently through the 2.875-inch flute length. With an overall length of 4.125 inches and a straight-cylindrical shank, this bit seats reliably in standard drill chucks. It carries a web-thinned, tapered web configuration and meets ANSI and NAS 907 standards, making it a heavy-duty general-purpose choice for machinists, pipefitters, and maintenance technicians who drill frequently in tough materials.

This bit is suited for production and maintenance drilling in steel, stainless steel, cast iron, non-ferrous metals, superalloys, and titanium. The steam oxide finish helps reduce friction and provides light corrosion resistance during storage. It is appropriate for use in drill presses, CNC machining centers, and handheld power drills where a straight-shank bit is required. The 11xD flute-to-diameter ratio keeps the bit stable in deeper passes up to the maximum drilling depth of 2.875 inches. Single-piece packaging makes it easy to add to a kit or replace a worn bit without over-ordering.

Key Features

• Letter I size — 0.272 inches decimal equivalent
• 135-degree split point reduces thrust and minimizes center-punch requirements
• Steam oxide coating lowers friction and provides light corrosion resistance
• Web-thinned tapered web improves chip evacuation and reduces heat buildup
• Meets ANSI and NAS 907 specifications for heavy-duty general-purpose drilling
• Right-hand cut, two-flute spiral with straight-cylindrical shank fits standard chucks

Compatibility

Designed for use in standard drill chucks accepting a 0.272-inch straight-cylindrical shank. Suitable for drilling steel, stainless steel, cast iron, non-ferrous metals, superalloys, and titanium per material codes P, M, K, N, and S.

Installation Notes

Licensed machinists and maintenance technicians typically install and replace jobber drill bits. Before changing a bit, power down and lock out or unplug the drilling equipment per OSHA lockout/tagout procedures. Secure the straight shank firmly in the chuck and verify concentricity before beginning a drilling operation. Use appropriate cutting fluid for hard materials such as stainless steel or titanium to extend bit life and reduce heat.