Chicago-latrobe 48928 7/16 Inch Hss Left Hand Drill Bit

Product Description

The CHICAGO-LATROBE 48928 is a screw machine length drill bit designed for general-purpose drilling in a wide range of materials. Built from high-speed steel (HSS) with a bright, uncoated finish, it features a 7/16 inch (0.4375 inch) diameter, a 118-degree standard point angle, and a left-hand cutting direction. The overall length is 3-7/16 inches, keeping it compact for use in tight spaces and screw machine applications. The web-thinned, parallel-web construction reduces thrust requirements at the point and improves chip clearance. Licensed tradespeople, machinists, and service technicians who work with left-hand extraction drilling will recognize this bit as part of the trusted Chicago-Latrobe Series 157L lineup.

This bit is suited for drilling into aluminum, copper, magnesium, slate, thermoplastic, and wood. The screw machine length format makes it a practical choice for turret lathes, CNC screw machines, and bench drill press work where reduced overhang improves rigidity and accuracy. Its left-hand cut is especially useful for removing broken fasteners, since the reverse rotation can back out a damaged stud or bolt as the bit makes contact. The straight shank and standard point geometry allow it to seat in any standard drill chuck sized for the 7/16 inch shank diameter.

Key Features

• Left-hand cutting direction for reverse-rotation drilling and broken fastener extraction
• HSS construction with bright, uncoated finish for general-purpose performance
• 118-degree standard point angle with web-thinned tip to reduce entry thrust
• Screw machine length (3-7/16 inches OAL) for improved rigidity in close-clearance work
• Regular spiral flute, 2-1/16 inch flute length, for consistent chip evacuation
• Straight shank (0.4375 inch diameter) fits standard drill chucks without adapters

Compatibility

Designed as an OEM-style general-purpose replacement or service bit compatible with any standard drill press, screw machine, turret lathe, or hand drill fitted with a chuck that accepts a straight shank of 7/16 inch diameter. Listed under Series 157L and meets ISO standards for drill geometry.

Installation Notes

Install this bit into a properly sized drill chuck and tighten with a chuck key before operation. Ensure the workpiece is securely clamped or fixtured before drilling. When using left-hand bits for fastener extraction, rotate the driving tool in reverse and apply steady downward pressure. Always wear appropriate eye protection and follow applicable ANSI and shop-safety requirements when operating cutting tools.