Chicago-latrobe 49211 Screw Machine Drill Bit Hss

Product Description

The CHICAGO-LATROBE 49211 is a screw machine length drill bit engineered for heavy-duty drilling in cast iron and steel. Built from high speed steel with a coated finish, it measures 0.1719 inches (11/64 inches) in diameter and carries a 135-degree split point that reduces walking and lowers thrust requirements at entry. The web-thinned, parallel-web construction improves chip evacuation and keeps the cutting edge stable under load. Overall length is 2.125 inches with a flute length of 1.0625 inches, making it the right choice when a stubby, rigid profile is needed in tight clearance or high-production applications. Diameter tolerance is held to +0.0000 to -0.0007 inches, meeting ISO and NAS 907 standards.

Screw machine length bits are standard in production machining, CNC drilling, and bench drill press work where a shorter flute length reduces deflection and increases hole accuracy. This bit is suited for drilling cast iron and steel in manufacturing, maintenance, and fabrication environments. The straight-cylindrical shank seats in standard three-jaw chucks and collet holders without modification. Series 159 is a heavy-duty line intended for repetitive, high-cycle drilling where bit life and dimensional consistency matter.

Key Features

• 135-degree split point reduces drill walking and lowers entry thrust on hard materials
• Web-thinned, parallel-web design improves chip flow and reduces heat buildup
• High speed steel construction with coated finish for extended wear life
• Screw machine (stub) length provides added rigidity and reduced deflection
• Diameter tolerance of +0.0000 to -0.0007 inches for consistent hole sizing
• Meets ISO and NAS 907 specifications for quality-controlled applications

Compatibility

Designed as an OEM-style replacement or direct-use drill bit for production and maintenance drilling operations in cast iron and steel workpieces requiring an 11/64-inch diameter hole.

Installation Notes

This bit is installed by machinists and maintenance technicians in drill presses, CNC machining centers, and hand-held power drills equipped with a standard three-jaw chuck. Secure the straight-cylindrical shank fully in the chuck before operation and verify runout is within acceptable limits for precision work. Always use appropriate cutting fluid or coolant when drilling steel at high cycle rates to preserve cutting edge life. Wear appropriate PPE including eye protection when operating.