Precision Twist Drill 5998889 Jobber Drill Bit Letter O

Product Description

The PRECISION TWIST DRILL 5998889 is a jobber length drill bit sized to Letter O (0.3160 inches decimal equivalent), designed for general-purpose drilling in a wide range of metalworking applications. Built from high speed steel with a bright uncoated finish, this bit features a 118-degree standard point angle and a two-flute right-hand spiral configuration. The web-thinned, tapered web design reduces thrust and improves chip evacuation at the point. Overall length is 4.5 inches, with a flute length of 3.1875 inches, giving it the extended reach typical of jobber series bits. Licensed HVAC technicians, machinists, pipefitters, and general tradespeople reach for jobber bits like this for everyday drilling tasks in metal fabrication, repair, and installation work.

This drill bit is suited for drilling steel, stainless steel, cast iron, non-ferrous metals, superalloys, titanium, and other hard materials. It fits into standard drill chucks via its straight cylindrical shank, which shares the same diameter as the cutting edge at 0.3160 inches. The bit belongs to the R10P-R15P-R18P series and meets ANSI standards, making it a reliable general-purpose choice for production or field use. Typical applications include clearance holes, through-holes, and pilot holes in structural and sheet metal components across HVAC, plumbing, electrical, and mechanical trades.

Key Features

• Letter O size with 0.3160 inch decimal equivalent for precise hole sizing
• 118-degree standard point angle for general-purpose metal drilling
• High speed steel construction handles steel, stainless steel, cast iron, non-ferrous metals, superalloys, and titanium
• Web-thinned tapered web reduces cutting thrust and improves point entry
• Right-hand spiral flute with regular spiral type promotes efficient chip removal
• Straight cylindrical shank fits standard 3-jaw drill chucks without adapters
• Meets ANSI specification standards for jobber length drill bits

Compatibility

Designed as a general-purpose jobber length drill bit compatible with any standard drill press, hand drill, or magnetic drill motor accepting a straight cylindrical shank. Part of the R10P-R15P-R18P series per ANSI jobber length standards.

Installation Notes

Install this bit into a properly sized drill chuck and tighten securely before operation. Ensure the workpiece is clamped or fixtured to prevent movement during drilling. Use appropriate cutting fluid or coolant when drilling stainless steel, superalloys, or titanium to extend bit life and reduce heat buildup. Inspect the cutting edges for wear before each use and replace the bit if chipping or dulling is observed.