Chicago-latrobe 48559 Screw Machine Drill Bit 59/64 Hss

Product Description

The CHICAGO-LATROBE 48559 is a screw machine length drill bit designed for high-volume drilling in metalworking applications. Built from high speed steel with a coated finish, this bit features a 59/64 inch (0.9219 inch) diameter and a standard 118-degree drill point angle. The shorter screw machine length format delivers increased rigidity compared to jobber-length bits, reducing deflection when drilling in drill presses, turret lathes, screw machines, and CNC machining centers. It is installed and used by machinists, toolroom technicians, and maintenance trades working with ferrous and non-ferrous metals.

This bit is rated for use on cast iron, non-ferrous metals, and steel. The screw machine length (also called stub length) design is well suited for production drilling environments where work is fixtured and tool overhang must be minimized. The 2-flute spiral design with web-thinned, parallel web geometry promotes chip evacuation and reduces thrust force during entry. It is a general purpose grade drill suited for both manual and CNC-driven applications where consistent hole quality across a range of workpiece materials is needed.

Key Features

• 59/64 inch (0.9219 inch) diameter with a diameter tolerance of +0.0000 to -0.0012 inches for controlled fit
• 118-degree standard point angle suited for general-purpose drilling in steel, cast iron, and non-ferrous metals
• High speed steel construction with coated finish for improved wear resistance
• Web-thinned parallel web reduces axial thrust and improves centering on entry
• Straight-cylindrical shank compatible with standard drill chucks and collet holders
• No coolant-through configuration — suitable for flood coolant or dry drilling setups

Compatibility

Designed as a general-purpose screw machine length drill bit for use in drill presses, turret lathes, screw machines, and CNC machining centers that accept a straight-cylindrical shank; primary workpiece materials include cast iron, non-ferrous metal, and steel.

Installation Notes

Installation and use of this drill bit should be performed by qualified machinists or maintenance technicians. Ensure the machine spindle is fully stopped and the chuck or collet is secure before inserting or removing the bit. Verify shank seating depth is adequate to prevent pullout under load. Follow applicable machine guarding requirements and wear appropriate eye protection when drilling.