Precision Twist Drill 5998854 Drill Bit Letter F Hss

Product Description

The PRECISION TWIST DRILL 5998854 is a jobber-length drill bit sized to Letter F (0.2570 inches decimal equivalent), designed for general-purpose drilling in a wide range of metal and hard 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 on entry. The 2-flute right-hand spiral flute geometry provides efficient chip evacuation during through-hole and blind drilling operations. Overall length is 4.125 inches with a 2.875-inch flute length. Licensed tradespeople and machinists reach for this bit when drilling steel, stainless, cast iron, and non-ferrous alloys on the bench or in the field.

This bit is suited for production and maintenance drilling in metalworking, HVAC fabrication, plumbing rough-in, and electrical trade work where a Letter F hole is required — for example, tapping 1/4-20 threads. The straight-cylindrical shank diameter of 0.2570 inches fits standard 3-jaw drill chucks on corded drills, drill presses, and CNC machines. It conforms to ANSI standards and belongs to the R10P-R15P-R18P series, a general-purpose HSS jobber line from Precision Twist Drill.

Key Features

• Letter F size — 0.2570 inches decimal equivalent, commonly used for 1/4-20 tap drilling
• 118-degree standard point angle with web-thinned, tapered web for reduced entry thrust
• High-speed steel construction handles steel, stainless steel, cast iron, non-ferrous metals, superalloys, and titanium
• Right-hand cut, regular spiral flute for positive chip removal in through and blind holes
• Bright uncoated finish — easy to inspect for wear and resharpen on a bench grinder
• ANSI-compliant jobber length — 4.125 inches OAL, 2.875-inch maximum drilling depth

Compatibility

Designed as a general-purpose jobber-length drill bit compatible with any standard 3-jaw drill chuck accepting a 0.2570-inch straight-cylindrical shank. Fits corded and cordless drills, drill presses, and CNC machining centers. Part of the Precision Twist Drill R10P-R15P-R18P series.

Installation Notes

Secure the shank fully in the chuck and verify concentricity before drilling. Use cutting fluid or coolant when drilling stainless steel, superalloys, or titanium to extend tool life, even though this bit does not have through-coolant capability. Clamp the workpiece firmly — never hand-hold metal stock during drilling. Inspect the cutting edges before each use and resharpen or replace when point geometry shows wear to maintain hole-size accuracy.