Chicago-latrobe 49097 Screw Machine Drill Bit 0.144 in

Product Description

The CHICAGO-LATROBE 49097 is a screw machine length drill bit designed for general-purpose drilling in a range of materials. Built from high speed steel with a bright/uncoated finish, it measures 0.144 inches in diameter and carries a wire gauge designation of #27. The 118-degree standard point angle provides a reliable starting geometry on flat and curved surfaces. With a 2-flute spiral flute design and a straight-cylindrical shank, this bit fits standard drill chucks without adapters. It is a left-hand cut tool, making it particularly useful for removing broken fasteners or reverse-drilling applications where right-hand bits are not appropriate. Machinists, maintenance technicians, and metalworking professionals are the primary installers and users.

This bit is suited for drilling aluminum, copper, magnesium, slate, thermoplastic, and wood. The screw machine length format — shorter overall than a jobber-length bit — provides added rigidity and reduced deflection, making it well suited for drill press, CNC, and turret lathe applications where chuck clearance and runout control matter. The web-thinned, parallel web configuration reduces thrust force at the cutting tip, which is especially beneficial when working in softer non-ferrous metals and plastics. It is a general-purpose grade bit appropriate for both production and maintenance environments.

Key Features

• Left-hand cut spiral flute for reverse-drilling and broken fastener extraction
• High speed steel construction with bright/uncoated finish for general-purpose use
• 118-degree standard point angle for broad material compatibility
• Web-thinned, parallel web reduces cutting thrust on entry
• Screw machine length body adds rigidity and reduces deflection vs. jobber length
• Straight-cylindrical shank fits standard 3-jaw and collet-style drill chucks

Compatibility

Designed for use in drill presses, CNC machines, turret lathes, and hand drills that accept straight-cylindrical shank bits. Compatible primary workpiece materials include aluminum, copper, magnesium, slate, thermoplastic, and wood. Part of the CHICAGO-LATROBE Series 157L screw machine drill line.

Installation Notes

This is a left-hand cut bit — confirm spindle rotation direction before use, as running it in a standard right-hand drill will not produce a cut and may damage the bit or workpiece. Secure the workpiece firmly before drilling to prevent material from spinning with the bit, particularly in softer materials. Use a center punch to establish a pilot point and minimize walking on hard or smooth surfaces. Follow applicable machine guarding and PPE requirements per shop safety standards when operating drilling equipment.