Chicago-latrobe 50840 Screw Machine Drill Bit 0.281 in

Product Description

The CHICAGO-LATROBE 50840 is a cobalt screw machine length drill bit designed for heavy-duty metal drilling in demanding shop and field applications. Built from M42 cobalt high-speed steel, it carries a 135-degree split point that reduces walking on entry and lowers the thrust force needed to start the cut. At 0.281 inches (9/32 inch, Letter K) in diameter, this bit handles cast iron, steel, and similarly tough workpiece materials with consistent performance. The parallel web configuration and web-thinned geometry support clean chip evacuation through the 1.5-inch spiral flute length. It is a standard tool for machinists, pipefitters, and fabricators who need reliable short-length drilling in tight clearance situations.

This bit is intended for use in screw machine, drill press, and hand-drill applications where a stub-length tool is required to minimize deflection and maximize rigidity. The straight cylindrical shank seats directly into standard drill chucks without modification. Its heavy-duty grade and cobalt construction make it well suited for production drilling in steel and cast iron, including hard-to-machine alloys where standard HSS bits wear prematurely. ISO standards apply to this series.

Key Features

• M42 cobalt construction for extended tool life in hard and abrasive metals
• 135-degree split point reduces walking and lowers entry thrust on hard materials
• Screw machine (stub) length minimizes deflection in tight or shallow setups
• Web-thinned, parallel web geometry supports efficient chip evacuation
• Right-hand cut, 2-flute spiral configuration for standard CW drilling
• Diameter tolerance of +0.0000 to -0.0010 inches for precise hole sizing

Compatibility

Designed as a direct-fit replacement for any 9/32-inch (Letter K, 0.281-inch) screw machine length drill bit with a straight cylindrical shank. Compatible with standard drill chucks in screw machines, drill presses, and hand drills. Part of the Chicago-Latrobe Series 559 heavy-duty cobalt line.

Installation Notes

Install in a properly sized drill chuck and tighten securely before operation. Power down and de-energize all equipment before changing tooling. Use appropriate cutting fluid or coolant on the workpiece when drilling steel or cast iron to extend tool life and maintain hole quality. Disposal of metal chips and worn tooling should follow applicable shop safety and local regulations.