Precision Twist Drill 5998537 Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5998537 is a screw machine length drill bit engineered for high-performance drilling in demanding trade and industrial applications. Manufactured from high speed steel with a coated finish, this bit measures 0.136 inches (No. 29 wire gauge) in diameter with an overall length of 1-15/16 inches and a flute length of 15/16 inches. The 135-degree split point reduces walking and allows faster penetration with less feed pressure. A tapered web with web thinning further reduces thrust requirements. Licensed machinists, tool-and-die techs, and maintenance professionals working with tight tolerances will find this bit well suited to precision hole-making tasks.

This screw machine length bit is designed for use in drill presses, CNC machining centers, turret lathes, and hand-held pneumatic drills where a shorter, stiffer tool is required to minimize deflection. The primary rated workpiece material is titanium, making it appropriate for aerospace, medical, and precision manufacturing environments where conventional bits fall short. The right-hand spiral flute efficiently evacuates chips during through-hole and blind-hole drilling operations. The 2.5xD flute-to-diameter ratio supports clean chip clearance in deeper bores relative to the stub-length body.

Key Features

• No. 29 wire gauge size — 0.136 inch diameter for precise, repeatable hole sizing
• 135-degree split point reduces thrust and eliminates center-punch requirement on many materials
• Web-thinned tapered web for reduced cutting resistance and improved chip flow
• High speed steel construction with coated finish for enhanced wear resistance
• Screw machine (stub) length for maximum rigidity and minimal deflection in close-clearance setups
• Meets ANSI and NAS 907 standards — heavy duty grade, Series R41C

Compatibility

Designed as a screw machine length replacement drill bit for use in standard straight-shank chuck systems rated for the 0.136 inch diameter range, conforming to ANSI and NAS 907 specifications.

Installation Notes

Installation of this bit is performed by machinists and maintenance technicians using standard three-jaw or collet-style chucks compatible with straight-cylindrical shanks. Ensure the spindle is fully stopped and power is locked out before changing bits. Secure the shank fully into the chuck to the maximum recommended insertion depth to prevent slippage and maintain concentricity. Follow applicable workplace safety standards and machine manufacturer guidelines for feed rate and speed settings appropriate to the workpiece material.