Precision Twist Drill 5998545 Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5998545 is a screw machine length drill bit designed for high-performance metal cutting in demanding shop and field applications. Manufactured from high speed steel with a coated finish, it measures 0.8281 inches (53/64 inch) in diameter with a 5-3/8 inch overall length and a 3-1/2 inch flute length. The 118-degree standard point angle and web-thinned, tapered web configuration reduce entry resistance and improve chip evacuation. A straight-cylindrical shank provides secure, concentric chuck seating in standard drill chucks and screw machine spindles. This bit is built to ANSI standards and rated for general purpose and high-performance drilling duty.

The 5998545 is suited for drilling titanium as its primary workpiece material, making it a capable choice for aerospace, manufacturing, and precision machining environments where harder materials are encountered. The screw machine length (stub) format offers increased rigidity compared to jobber-length bits, which reduces deflection and improves hole accuracy in short-reach setups. The regular spiral flute geometry at a 2.5xD flute-to-diameter ratio handles chip clearance efficiently during through-hole and blind-hole operations. Machinists, toolroom technicians, and production drill press operators will find this bit well suited to fixture-mounted and hand-fed screw machine work.

Key Features

• 53/64 inch (0.8281 inch) diameter with ANSI-standard tolerances
• High speed steel construction with coated finish for extended tool life
• 118-degree standard point angle with web-thinned, tapered web for reduced thrust
• Screw machine (stub) length format for maximum rigidity and reduced deflection
• Right-hand cut, regular spiral flute with 2.5xD flute ratio for efficient chip removal
• Straight-cylindrical shank fits standard drill chucks without adapters
• Rated for titanium and other demanding workpiece materials

Compatibility

Designed as an OEM-style replacement and standard production drill bit for screw machine and drill press applications requiring a 53/64 inch straight-shank bit; compatible with any standard drill chuck or screw machine spindle accepting a straight-cylindrical shank of this diameter.

Installation Notes

Installation and use should be performed by qualified machinists or toolroom technicians familiar with drill press, turret lathe, or screw machine operation. Secure the shank fully in the chuck and verify runout before drilling. Always follow appropriate personal protective equipment practices and machine guarding requirements when operating rotating cutting tools. When drilling titanium or similar hard materials, use appropriate cutting fluid and controlled feed rates to prevent work hardening and premature tool wear.