Precision Twist Drill 5998572 Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5998572 is a screw machine length drill bit designed for high-performance drilling in metal fabrication and machining applications. Ground from high speed steel (HSS) with a bright, uncoated finish, this bit features a 118-degree standard point angle and a web-thinned, tapered web configuration that reduces thrust and improves chip clearance at the start of the cut. The straight cylindrical shank seats securely in standard drill chucks or screw machine spindles. At 0.25 inches (1/4 inch, Letter E) in diameter with a 2.5 times diameter flute-to-diameter ratio, this bit delivers consistent performance on demanding materials.

This bit is suited for screw machine operations, CNC drilling centers, and manual drill press work in job shop or production environments. Its shorter screw machine length provides increased rigidity compared to jobber-length bits, making it a preferred choice when drilling in tight clearances or high-cycle applications. The primary workpiece material rating is titanium, indicating suitability for ferrous and non-ferrous metals including steel, aluminum, and harder alloys. It conforms to ANSI standards and is sold individually.

Key Features

• High speed steel construction for durability across a wide range of metals
• 118-degree standard point angle with web thinning for reduced entry thrust
• Screw machine length for added rigidity in production drilling setups
• Bright/uncoated finish suitable for general purpose applications
• Right-hand spiral flute for efficient chip evacuation
• Conforms to ANSI standards, Series R40

Compatibility

Designed as a general purpose screw machine length drill bit compatible with standard straight-shank drill chucks, screw machine spindles, and CNC tool holders accepting 0.25 inch straight cylindrical shanks.

Installation Notes

Installation and use of this drill bit should be performed by qualified machinists or trade professionals familiar with drill press, screw machine, or CNC equipment operation. Secure the shank fully in the chuck and verify runout before drilling. Use appropriate cutting fluid or coolant for the workpiece material to extend tool life, noting this bit does not support through-coolant delivery. Follow applicable shop safety practices and machine manufacturer guidelines when setting spindle speed and feed rate.