Chicago-latrobe 50843 Screw Machine Drill Bit 0.302 in Cobalt

Product Description

The CHICAGO-LATROBE 50843 is a cobalt screw machine length drill bit sized at 0.302 inches (Letter N) with a 135-degree split point. It is built for heavy-duty drilling in ferrous materials including cast iron and steel. The shortened screw machine length improves rigidity and reduces deflection in close-tolerance work. Two spiral flutes with web thinning and a parallel web configuration promote chip evacuation and reduce thrust load. The split point geometry allows the bit to start without center-punching, keeping hole placement accurate on hard or scale-covered surfaces. Licensed HVAC, plumbing, electrical, and mechanical trades rely on this style of bit for repetitive hole production in fabrication and field service environments.

The 50843 is suited for production drilling and maintenance work on cast iron and steel workpieces. Its screw machine length — 2-13/16 inches overall with a 1-5/8 inch flute length — makes it a natural fit for drill press work, turret lathes, screw machine setups, and handheld drilling where stub rigidity is needed. Right-hand cut and straight-cylindrical shank ensure compatibility with standard drill chucks and collet holders used across trades. The Series 559 designation identifies it within CHICAGO-LATROBE's heavy-duty cobalt line, which is manufactured to ISO standards.

Key Features

• M42 cobalt tool material rated for heavy-duty drilling in cast iron and steel
• 135-degree split point starts on contact without center-punching
• Web-thinned parallel web lowers thrust and extends bit life in hard materials
• Screw machine length (2-13/16 inches overall) maximizes rigidity and minimizes deflection
• Right-hand cut with straight-cylindrical shank fits standard chucks and collet holders
• Diameter tolerance of +0.0000 to -0.0010 inches supports close-tolerance hole work

Compatibility

Designed for use in standard drill chucks and collet holders accepting a straight-cylindrical shank. Primary workpiece materials are cast iron and steel as stated by the manufacturer.

Installation Notes

Install the straight-cylindrical shank into a properly sized drill chuck or collet and tighten securely before operation. Use appropriate cutting fluid or coolant when drilling steel to manage heat buildup, as the bit is not coolant-through rated. Secure the workpiece firmly before starting the cut. Observe applicable shop-safety and OSHA requirements for rotating tool operation.