Chicago-latrobe 49105 Screw Machine Drill Bit 0.110 in Lh

Product Description

The CHICAGO-LATROBE 49105 is a screw machine length drill bit designed for left-hand cutting in general-purpose drilling applications. Built from high speed steel with a bright, uncoated finish, it measures 0.110 inches (7/64 inch, wire size 35) in diameter with an overall length of 1.875 inches and a flute length of 0.875 inches. The 118-degree split point and web-thinned geometry reduce entry force and improve centering on contact. The straight-cylindrical shank seats in standard drill chucks. This bit is sized and configured for use by machinists, maintenance technicians, and trade professionals working with precision fastener extraction or left-hand drilling tasks.

The 49105 is suited for drilling in aluminum, copper, magnesium, slate, thermoplastic, and wood. The screw machine length format provides a shorter, more rigid profile compared to jobber-length bits, making it well-suited for close-quarters drilling, drill press work, and CNC or turret lathe operations where rigidity and runout control matter. Left-hand rotation assists in backing out broken fasteners and studs when used with a reversible drill.

Key Features

• Left-hand cutting direction aids in broken fastener extraction
• High speed steel construction for general-purpose metal and non-metal drilling
• 118-degree standard point angle with web thinning for reduced thrust force
• Screw machine (stub) length profile increases rigidity and reduces deflection
• Bright uncoated finish suitable for use with cutting fluids or dry
• Parallel web configuration and regular spiral flute for consistent chip evacuation

Compatibility

Designed for use in standard straight-shank drill chucks on reversible hand drills, drill presses, and turret lathes. Compatible with primary workpiece materials including aluminum, copper, magnesium, slate, thermoplastic, and wood per manufacturer specification. Manufactured to ISO standards with a diameter tolerance of +0.0000 to -0.0005 inches.

Installation Notes

Secure the straight-cylindrical shank fully in the chuck before operation and verify the drill is set to reverse rotation for left-hand cutting. Always wear appropriate eye protection and secure the workpiece before drilling. When using this bit for fastener extraction, center-punch the fastener first to prevent the bit from walking. Inspect the cutting edges before each use and replace the bit if chipping or wear is evident.