Chicago-latrobe 48916 Screw Machine Drill Bit 1/4 in Hss

Product Description

The CHICAGO-LATROBE 48916 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, this bit features a 1/4 inch (0.2500 inch) diameter and a left-hand cutting direction, making it the correct choice for applications that require reverse-rotation drilling, such as removing broken fasteners. The 118-degree drill point angle and web-thinned geometry support accurate starting and efficient chip evacuation. At 2.5 inches overall length, the stub-length body provides added rigidity over jobber-length bits in tight-clearance setups. Machinists, maintenance technicians, and trade professionals install this bit in compatible drill presses, CNC equipment, and handheld power tools.

The 48916 is suited for drilling aluminum, copper, magnesium, slate, thermoplastic, and wood. The screw machine length format is commonly selected when working in confined spaces or when additional bit rigidity is needed to reduce deflection. The straight shank fits standard drill chucks without adapters, and the regular spiral flute promotes smooth chip removal during through-hole operations. This bit fits general-purpose production and maintenance workflows across machining, HVAC, plumbing, and electrical trades.

Key Features

• Left-hand cutting direction for reverse-rotation applications and broken fastener extraction
• HSS construction with bright, uncoated finish for general-purpose material compatibility
• 118-degree standard point angle with web-thinned tip for accurate bit start and reduced thrust
• Screw machine (stub) length body at 2.5 inches OAL provides greater rigidity than jobber-length bits
• Regular spiral flute with parallel web configuration for consistent chip evacuation
• Straight shank fits standard drill chucks without adapters

Compatibility

Designed as a general-purpose left-hand screw machine drill bit compatible with standard straight-shank drill chucks on drill presses, CNC drilling equipment, and handheld power tools. Suitable for use in aluminum, copper, magnesium, slate, thermoplastic, and wood workpieces per Series 157L specifications.

Installation Notes

This bit is installed and operated by machinists and trade technicians using standard drill press or handheld power tool equipment. Secure the straight shank firmly in a keyed or keyless chuck before operation and verify left-hand rotation is engaged on the drive tool before use. Wear appropriate eye protection and secure the workpiece to prevent movement during drilling. Do not exceed the recommended speed range for the workpiece material to avoid premature bit wear or breakage.