Precision Twist Drill 5998641 Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5998641 is a screw machine length drill bit designed for high-performance metal removal in industrial and trade applications. Manufactured from high speed steel with a bright/uncoated finish, this bit features a 21/32 inch (0.6562 inch) diameter, a 118-degree standard point angle, and a web-thinned tapered web configuration that reduces thrust and improves chip clearance. The straight-cylindrical shank seats securely in standard drill chucks. At 4.5 inches overall length with a 2.875-inch flute length, the screw machine format offers greater rigidity than jobber-length bits, making it well suited to close-tolerance drilling operations.

This drill bit is appropriate for use in machining shops, maintenance facilities, and field service environments where short, rigid tooling is preferred. The Series R40 designation and ANSI standard compliance indicate a general-purpose high-performance grade suitable for ferrous and non-ferrous metals. The primary workpiece material rating includes titanium, making it a capable choice for harder alloy work where a standard jobber-length bit may deflect. It is typically installed in a drill press, milling machine, or handheld drill with a compatible chuck capacity for 21/32-inch diameter shanks.

Key Features

• 21/32 inch (0.6562 inch) diameter with 118-degree standard point angle for broad material compatibility
• Web-thinned tapered web reduces entry thrust and improves chip evacuation
• High speed steel construction for durability across ferrous and non-ferrous applications
• Screw machine length (4.5 inches overall) provides enhanced rigidity over jobber-length formats
• Right-hand spiral flute with 2.5xD flute-to-diameter ratio promotes consistent chip flow
• ANSI-compliant Series R40, bright/uncoated finish, no coolant-through requirement

Compatibility

Designed as an OEM-style replacement and general-purpose screw machine length drill bit for use in standard drill chucks and collet systems accepting a straight-cylindrical shank at 21/32 inch diameter.

Installation Notes

Installation and use should be performed by a qualified machinist or experienced tradesperson familiar with rotating cutting tool safety. Secure the shank fully in the chuck and verify runout before operation. Follow applicable ANSI machining safety standards and wear appropriate eye protection. Inspect the cutting edges for wear or chipping before each use and replace the bit if the point geometry is compromised.