Chicago-latrobe 54077 Cobalt Jobber Drill Bit No. 42

Product Description

The CHICAGO-LATROBE 54077 is a cobalt jobber-length drill bit sized to wire gauge No. 42 (0.0935 inches decimal), designed for drilling stainless steel and other hard steels where standard high-speed steel bits fall short. Built to M42 cobalt material grade, the bit carries a titanium nitride (TiN) coating that extends cutting life and reduces friction at the tool interface. The 135-degree split point geometry allows precise starting without a center punch and reduces walking on hard, smooth surfaces. Overall length is 2.25 inches with a 1.25-inch flute length. This bit is intended for use by machinists, maintenance technicians, and fabricators working in metal-intensive applications.

The 54077 is suited for production and maintenance drilling in stainless steel and general-purpose steel in both shop and field environments. The straight-cylindrical shank at 0.0935 inches diameter fits standard keyless or keyed chucks without adapters. Its regular spiral flute and tapered web configuration handle chip evacuation efficiently in short-hole drilling operations. The Series 2550 designation places this bit within a heavy-duty, high-performance product family built to DIN 338 and NAS 907 Type J standards, making it appropriate for aerospace, industrial maintenance, and precision fabrication work.

Key Features

• M42 cobalt construction resists heat buildup when drilling stainless steel and alloy steels
• TiN coating reduces friction and extends tool life compared to uncoated cobalt bits
• 135-degree split point for self-centering starts and reduced thrust force
• Web-thinned, tapered web configuration promotes chip evacuation in deep cuts
• Right-hand spiral flute, 2-flute design for standard drilling operations
• Meets DIN 338 and NAS 907 Type J standards; M42 grade for heavy-duty applications

Compatibility

Designed as a jobber-length replacement or production bit for applications requiring a No. 42 wire gauge (0.0935-inch) drill in stainless steel, carbon steel, and similar ferrous materials. Compatible with any standard chuck accepting a 0.0935-inch straight-cylindrical shank.

Installation Notes

Secure the shank fully in a keyed or keyless drill chuck before operation and verify runout before drilling into finished workpieces. Reduce spindle speed and apply cutting fluid when drilling stainless steel to prevent work hardening at the entry point. Inspect the cutting edges before each use; cobalt bits can chip if forced through hardened material without adequate feed pressure. Disposal of worn or broken bits should follow shop safety procedures for sharp metal waste.