Chicago-latrobe 50903 Screw Machine Drill Bit 0.076 in

Product Description

The CHICAGO-LATROBE 50903 is a cobalt screw machine length drill bit designed for high-performance drilling in ferrous metals and hard materials. Sized at 0.076 inches in diameter (Wire Size 48), it features a 135-degree split point that reduces walking and minimizes the need for a center punch. The M42 cobalt grade construction provides heat resistance for sustained cutting in tough materials such as cast iron and steel. At 1-11/16 inches overall length and an 11/16-inch flute length, this stub-length geometry delivers added rigidity for accurate, chatter-free holes in production and maintenance environments. Licensed trades and metalworking shops rely on this bit for close-tolerance drilling where standard HSS tooling falls short.

This bit is built for drilling cast iron and steel in screw machine operations, CNC setups, drill presses, and hand drilling applications that demand a short, stiff bit profile. The Series 559 heavy-duty classification makes it suitable for production runs and repetitive operations where tool life and dimensional consistency are priorities. Its straight-cylindrical shank fits standard drill chucks without modification, and its web-thinned, parallel web design promotes efficient chip evacuation through the two-flute spiral configuration.

Key Features

• M42 cobalt construction for extended tool life in cast iron and steel
• 135-degree split point reduces drill walk and cutting force
• Web-thinned parallel web improves chip evacuation and reduces thrust load
• Screw machine (stub) length provides maximum rigidity for tight-tolerance applications
• Right-hand cut, two-flute regular spiral flute design for standard drilling operations
• Diameter tolerance of plus 0.0000 to minus 0.0005 inches for consistent hole sizing
• ISO-standard compliant construction

Compatibility

Designed for use in standard drill chucks accepting a straight-cylindrical shank. Primary workpiece materials are cast iron and steel. Fits applications calling for a Wire Size 48 or 0.0760-inch diameter drill bit in screw machine length.

Installation Notes

Install in a properly rated drill chuck and verify chuck is fully tightened before operation. Power down and de-energize the machine before bit changes. Use appropriate cutting fluid or coolant for steel and cast iron to maximize tool life, noting that this bit does not support coolant-through operation. Follow applicable shop safety standards and machine manufacturer guidelines for speed and feed rates.