Precision Twist Drill 5998863 Jobber Drill Bit Letter I

Product Description

The PRECISION TWIST DRILL 5998863 is a jobber length drill bit sized to letter I (0.2720 inches), designed for general-purpose drilling in a wide range of materials. Built from high speed steel with a bright uncoated finish, it features a standard 118-degree split point and a tapered web-thinned design that reduces thrust and improves centering on entry. The straight-cylindrical shank measures 0.2720 inches in diameter, and the overall length is 4.125 inches. Two spiral flutes in a regular helix pattern clear chips efficiently during through-hole and blind-hole drilling. This bit is suited for machinists, fabricators, and maintenance technicians working in production or field environments.

This drill bit is intended for right-hand drilling operations on a standard drill press, CNC machining center, or hand drill. Compatible workpiece materials include steel, stainless steel, cast iron, non-ferrous metals, superalloys, and titanium. With a flute length of 2.875 inches and a maximum drilling depth of 2.875 inches, it covers most jobber-depth applications without the need for a longer series bit. The Series R10P-R15P-R18P designation places it within a well-established general-purpose high speed steel product family conforming to ANSI standards.

Key Features

• Letter I size at 0.2720 inches decimal equivalent for precise hole sizing
• 118-degree standard point angle with web thinning for reduced entry thrust
• High speed steel construction handles steel, stainless steel, cast iron, non-ferrous metals, superalloys, and titanium
• Right-hand cut with regular spiral flutes for efficient chip evacuation
• Straight-cylindrical shank fits standard drill chucks without adapters
• ANSI-conforming geometry; no coolant-through requirement simplifies setup

Compatibility

Designed as a general-purpose jobber length drill bit for use in standard three-jaw drill chucks on drill presses, lathes, CNC machining centers, and hand drills accepting a 0.2720-inch straight shank.

Installation Notes

Installation is performed by machinists or maintenance technicians familiar with rotating cutting tools. Secure the shank fully in the chuck and confirm runout before cutting. Always wear appropriate eye protection and secure the workpiece before drilling. Do not exceed the rated maximum drilling depth of 2.875 inches in a single pass; use a peck-drilling cycle when operating near maximum depth to clear chips and reduce heat buildup.