Precision Twist Drill 5999437 Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5999437 is a screw machine length drill bit engineered for high-performance drilling in demanding trade and industrial applications. Manufactured from high speed steel (HSS) with a coated finish, this bit measures 0.3906 inches (25/64 inch) in diameter and features a 135-degree split point with web thinning for fast, accurate starts and reduced thrust. The shorter screw machine length body — 3.25 inches overall with a 1.875-inch flute length — provides added rigidity in drill press, CNC, and turret lathe setups where stub length tools are preferred. Series R40C with tapered web configuration and regular spiral flutes makes this a go-to bit for production drilling environments.

This drill bit is rated for primary use in titanium and other high-performance workpiece materials where a heavy-duty, web-thinned HSS bit is required. The straight-cylindrical shank fits standard drill chucks without an adapter. It is well suited for machine shop environments, maintenance and repair operations, and trade professionals working with precision-tolerance hole requirements. The right-hand spiral flute evacuates chips efficiently during through-hole and blind-hole drilling in both manual and automated setups. The 2.5xD flute-to-diameter ratio supports chip clearance in deeper cuts without the added length of a jobber bit.

Key Features

• 135-degree split point with web thinning for self-centering starts and reduced walking
• High speed steel construction with coated finish for extended tool life
• Screw machine (stub) length body for increased rigidity in fixed-spindle setups
• Tapered web configuration with regular spiral flutes for efficient chip evacuation
• Straight-cylindrical shank fits standard drill chucks directly
• Meets ANSI and NAS 907 standards for dimensional and performance compliance

Compatibility

Designed as an OEM-style screw machine length drill bit for use in drill presses, CNC machining centers, turret lathes, and manual drill chucks accepting a straight-cylindrical shank. Rated for titanium as the primary workpiece material; suitable for other metals within the heavy-duty HSS performance range. Fits the 0.3500 to 0.4000 inch decimal inch drill size range.

Installation Notes

Installation and use should be performed by qualified machinists or trade professionals familiar with rotating cutting tools. Always power down and lock out the spindle before changing or seating the bit in the chuck. Ensure the shank is fully seated and the chuck is tightened securely before beginning a cut. Follow applicable ANSI and shop safety standards for drill speed, feed rate, and coolant use appropriate to the workpiece material.