Precision Twist Drill 5998866 Jobber Drill Bit Letter J

Product Description

The PRECISION TWIST DRILL 5998866 is a jobber-length drill bit sized to letter J (0.2770 inches decimal equivalent), designed for general-purpose drilling in a wide range of materials. Built from high speed steel with a bright uncoated finish, this bit features a standard 118-degree split-point geometry and a two-flute spiral configuration with a tapered, web-thinned web for improved chip evacuation and reduced thrust. The straight-cylindrical shank measures 0.2770 inches in diameter and 1.25 inches in length, making it compatible with standard drill chucks. Overall length is 4.125 inches with a flute length of 2.875 inches, supporting a maximum drilling depth of 2.875 inches. This bit is suited for use by machinists, maintenance technicians, and fabricators requiring consistent, repeatable hole sizing.

The 5998866 is appropriate for drilling operations in steel, stainless steel, cast iron, non-ferrous metals, superalloys, titanium, and other hard materials. Its general-purpose grade and ANSI-compliant construction make it a reliable choice for production and maintenance drilling in job shops, fabrication facilities, and industrial maintenance environments. The regular spiral type and 10xD flute-to-diameter ratio support effective chip removal across a broad range of workpiece materials. Coolant-through capability is not available on this bit.

Key Features

• Letter J size with 0.2770 inch decimal equivalent for precise hole sizing
• 118-degree standard point angle with web-thinned, tapered web for lower entry thrust
• High speed steel construction rated for steel, stainless steel, cast iron, non-ferrous metals, superalloys, and titanium
• Two-flute regular spiral design with 2.875 inch flute length for efficient chip evacuation
• Straight-cylindrical shank fits standard three-jaw drill chucks without adapters
• ANSI-compliant geometry; Series R10P-R15P-R18P

Compatibility

Designed as a general-purpose jobber-length drill bit compatible with standard drill chucks accepting a 0.2770 inch straight-cylindrical shank. Suitable for benchtop drill presses, floor-standing drill presses, CNC machining centers, and hand-held power drills configured for this shank size.

Installation Notes

Installation and use of this drill bit should be performed by qualified machinists or trained technicians following applicable shop safety protocols. Secure the shank fully in the chuck and verify concentricity before beginning a drilling operation. Always match spindle speed and feed rate to the workpiece material and bit diameter per standard machining practice. Wear appropriate eye protection and ensure the workpiece is properly fixtured before drilling.