Precision Twist Drill 5998580 Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5998580 is a screw machine length drill bit engineered for high-performance drilling in demanding trade and industrial applications. Built from high speed steel with a coated finish, this bit features a 135-degree split point and web-thinned, tapered web construction that reduces walking and improves penetration on hard or tough materials. At 0.0995 inches in diameter (wire size 39), it is designed for precision hole placement in tight tolerances. Licensed machinists, tool-and-die technicians, and maintenance tradespeople working with CNC machines, drill presses, or hand-held equipment rely on this series for consistent performance in short-length stub drilling tasks.

This drill bit is rated for primary use in titanium workpieces and is suited to applications where a shorter flute-to-diameter ratio improves rigidity and reduces deflection. The R41C series carries a heavy-duty grade designation and conforms to ANSI and NAS 907 standards, making it appropriate for aerospace-adjacent maintenance work, precision machining shops, and industrial facility maintenance. The straight-cylindrical shank seats securely in standard keyless or keyed drill chucks without modification. At 1-13/16 inches overall length with a 13/16-inch flute length, it fits in confined setups where standard-length bits would be impractical.

Key Features

• 135-degree split point reduces thrust and minimizes walking on hard materials
• Web-thinned tapered web improves chip evacuation and cutting efficiency
• High speed steel construction with coated finish for extended tool life
• Screw machine (stub) length provides added rigidity and reduced deflection
• Right-hand spiral flute geometry with 2.5xD flute-to-diameter ratio
• Meets ANSI and NAS 907 standards for heavy-duty, high-performance applications

Compatibility

Designed as an OEM-style replacement or direct-use drill bit for any standard drill chuck accepting a straight-cylindrical shank; rated by the manufacturer for primary workpiece material of titanium and consistent with general-purpose ferrous and non-ferrous metal drilling in the R41C series.

Installation Notes

Install in a keyed or keyless drill chuck sized for a straight-cylindrical shank and ensure the chuck is fully tightened before operation. Power down or de-energize the machine tool completely before changing bits. Use appropriate cutting fluid when drilling titanium or other hard alloys to manage heat buildup and extend tool life. Follow applicable shop safety standards and machine guarding requirements during operation.