Chicago-latrobe 48520 Screw Machine Drill Bit 5/16 in Hss

Product Description

The CHICAGO-LATROBE 48520 is a screw machine length drill bit designed for high-speed steel drilling in cast iron, non-ferrous metals, and steel. At 5/16 inch (0.3125 inches) in diameter, this Series 157 bit features a 118-degree standard point angle, a bright/uncoated finish, and a web-thinned parallel web for improved penetration and chip clearance. The straight-cylindrical shank seats cleanly in standard drill chucks. At 2-13/16 inches overall length, the stub-length body delivers added rigidity over jobber-length bits, reducing deflection in tight spots. Machinists, maintenance mechanics, and metalworking tradespeople use this bit for production drilling where hole accuracy and tool life are both priorities.

The 48520 is suited for screw machine operations, CNC drilling fixtures, drill press work, and general-purpose metal fabrication. Its 1-5/8 inch flute length handles typical through-hole and blind-hole depths in structural steel, cast iron housings, aluminum, brass, and other non-ferrous stock. The right-hand spiral flute geometry evacuates chips efficiently, making it a practical choice for repetitive hole cycles in manufacturing and maintenance environments. This bit ships individually and is ordered in multiples of six.

Key Features

• 5/16 inch (0.3125 inches) diameter with a tight diameter tolerance of +0.0000 to -0.0010 inches for consistent hole sizing
• 118-degree standard point angle with web-thinned parallel web for easier penetration and reduced thrust
• High speed steel construction rated for cast iron, non-ferrous metals, and steel
• Screw machine (stub) length body increases rigidity and reduces deflection compared to jobber-length bits
• Bright/uncoated finish for use with standard cutting fluids or dry drilling
• Right-hand cut, 2-flute regular spiral flute design for efficient chip evacuation

Compatibility

Designed as a general-purpose screw machine length drill bit compatible with standard drill chucks and collet holders that accept straight-cylindrical shanks. Meets ISO standards for dimensional conformance.

Installation Notes

Installation and use should be performed by qualified machinists or metalworking tradespeople familiar with drill press, lathe turret, or CNC drilling operations. Secure the straight shank firmly in the chuck before operation and verify runout before drilling production holes. Use appropriate cutting fluid for the workpiece material to extend tool life and maintain hole tolerance. Inspect the cutting edges for wear regularly and avoid forcing a dull bit, which can cause oversized holes or tool breakage.