Chicago-latrobe 50857 Screw Machine Drill Bit 0.221 in

Product Description

The CHICAGO-LATROBE 50857 is a cobalt screw machine length drill bit engineered for heavy-duty metal drilling applications. Manufactured from M42 cobalt high-speed steel, it delivers superior heat resistance and edge retention when cutting through cast iron and steel. The bit measures 0.221 inches (Wire Size 2) in diameter with an overall length of 2-7/16 inches and a flute length of 1-5/16 inches. The 135-degree split point reduces walking on entry and minimizes thrust force, while the web-thinned, parallel-web geometry improves chip evacuation in production drilling environments. This is a right-hand cut, spiral-flute bit on a straight-cylindrical shank and conforms to ISO standards.

This drill bit is designed for use in screw machine operations, CNC drilling, and high-cycle production environments where tool life and dimensional accuracy are critical. Primary workpiece materials include cast iron and steel. The shortened screw machine length profile provides added rigidity compared to jobber-length bits, making it well-suited for close-tolerance work in lathe turrets, gang drill fixtures, and tight-access machining setups. It is sold individually and is a fit for machine shops, maintenance technicians, and trade professionals requiring a reliable cobalt bit for ferrous materials.

Key Features

• M42 cobalt steel construction for extended tool life in ferrous materials
• 135-degree split point reduces entry thrust and eliminates center-punch requirement on most metals
• Web-thinned parallel web improves chip flow and reduces heat buildup
• Screw machine length body adds rigidity over jobber-length bits for tighter tolerances
• Diameter tolerance held to +0.0000 to -0.0007 inches for precision-fit applications
• ISO-conforming Series 559 geometry suited for high-cycle production use

Compatibility

Designed as a direct-fit screw machine drill bit for standard straight-shank drill chucks and lathe turret tooling accepting a 0.221-inch straight-cylindrical shank. Primary workpiece compatibility is cast iron and steel per Series 559 specifications.

Installation Notes

Installation is performed by machinists, maintenance mechanics, and tool-and-die trades using standard drill press, lathe, or CNC equipment with a compatible straight-shank chuck. Ensure the spindle and workpiece are properly secured before engaging the drill. Run speeds should be selected per accepted cutting-speed tables for cobalt tooling on the specific workpiece material. Inspect the cutting edge before each use and replace the bit if chipping or excessive wear is present.