Precision Twist Drill 5998601 Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5998601 is a screw machine length, high speed steel drill bit designed for high-performance metal drilling applications. It features a 0.161 inch (wire gauge #20) diameter with a 135-degree split point for fast, accurate starting without a center punch. The web-thinned, tapered web construction reduces thrust and improves chip evacuation. At 2.125 inches overall length with a 1.0625 inch flute length, this bit is built for short-hole, high-volume production drilling where rigidity and repeatability matter. It is right-hand cut with a straight-cylindrical shank and a regular spiral flute pattern.

This drill bit is rated for primary workpiece material in titanium and other hard metals, making it well suited for aerospace, machining, and fabrication environments. The Series R41C designation and NAS 907 specification number indicate conformance to ANSI and NAS standards, which are common requirements in production and defense-adjacent manufacturing settings. The 2.5xD flute-to-diameter ratio provides added chip clearance during short-hole drilling cycles. This bit ships individually and is ordered in multiples of 12.

Key Features

• 135-degree split point for self-centering entry and reduced walking
• Web-thinned, tapered web reduces drilling thrust on hard materials
• High speed steel construction rated for titanium and hard metal applications
• Screw machine length (2.125 inches overall) for maximum rigidity in production setups
• Right-hand cut, regular spiral flute for efficient chip removal
• Meets ANSI and NAS 907 specifications for dimensional and performance standards

Compatibility

Designed as an OEM-style screw machine length drill bit for use in standard straight-shank drill chucks and production drilling fixtures accepting a straight-cylindrical shank at 0.161 inch diameter.

Installation Notes

This bit is installed and operated by machinists and tool-and-die professionals using compatible drill presses, CNC machining centers, or hand-held pneumatic drills with appropriate chuck capacity. Ensure the workpiece is securely fixtured before drilling to prevent bit walking or breakage. Use appropriate cutting fluid or coolant for titanium and hard metal applications to manage heat buildup. Inspect bit tip for wear or chipping before each use and replace at first sign of dulling to maintain hole quality.