Precision Twist Drill 5998528 Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5998528 is a screw machine length drill bit designed for high-performance drilling in demanding industrial and trade applications. Built from high speed steel with a coated finish, this bit measures 0.144 inches (wire size 27) in diameter with an overall length of 2-1/16 inches and a flute length of 1 inch. The 135-degree split point reduces walking on contact and requires less feed pressure at entry. The web-thinned, tapered web construction improves chip evacuation and cutting efficiency. Licensed machinists, tool-and-die technicians, and mechanical contractors working in tight-clearance or high-cycle environments will find this bit well-suited to production drilling tasks.

This screw machine length bit is rated for primary use in titanium workpieces, making it a capable choice for aerospace, precision machining, and industrial maintenance applications where shorter bit length reduces deflection and improves hole accuracy. The reduced overall length compared to a jobber-length bit provides added rigidity in drill presses, CNC machines, and hand-held power tools working in constrained spaces. The right-hand spiral flute and straight cylindrical shank allow direct chucking in standard three-jaw and keyless chucks without adapters.

Key Features

• 0.144 inch diameter, wire size 27, for close-tolerance hole sizing
• 135-degree split point reduces center punch requirement and minimizes walking
• Web-thinned tapered web improves chip flow and reduces thrust in hard materials
• High speed steel construction with coated finish for extended tool life
• Screw machine length body (2-1/16 inches overall) provides extra rigidity over jobber-length bits
• Meets ANSI and NAS 907 standards; rated for titanium primary workpiece material

Compatibility

Designed as a screw machine length replacement or production-run drill bit for standard three-jaw chucks and keyless chucks accepting straight cylindrical shanks. Fits drill presses, CNC drilling centers, and hand-held power tools with appropriate chuck capacity. Series R41C, ANSI and NAS 907 compliant.

Installation Notes

Secure the straight cylindrical shank firmly in the chuck before operation and verify runout is within acceptable tolerance for the application. When drilling titanium or other work-hardening materials, use appropriate cutting fluid and consistent feed pressure to prevent work hardening at the drill tip. Inspect the split point and cutting edges before each use; a dull or chipped bit in hard material can cause rapid tool failure or workpiece damage. Follow applicable ANSI and shop safety standards for machine guarding and personal protective equipment when operating drilling equipment.