Precision Twist Drill 5996092 Cobalt Drill No.42 6in

Product Description

The PRECISION TWIST DRILL 5996092 is a cobalt aircraft extension drill bit designed for drilling through hard and abrasive materials where standard high-speed steel tooling falls short. Sized to wire gauge No. 42 with a decimal diameter of 0.0935 inches, the bit features a 135-degree split point for fast, self-centering starts without a center punch. A straw finish indicates the cobalt content and heat treatment level. The straight-cylindrical shank seats securely in standard drill chucks. This is a two-flute, right-hand cutting drill with a spiral flute design and tapered web configuration, built to Series CO501-6 standards and conforming to NAS 907 Type J.

This drill bit is suited for aerospace, sheet metal, and general precision-hole work where a wire-gauge No. 42 diameter is specified. The extended 6-inch overall length allows access to deep or recessed locations that standard-length bits cannot reach. The 1.25-inch flute length and 4xD flute-to-diameter ratio provide adequate chip evacuation in short-hole applications at this diameter. It is typically used by machinists, aviation maintenance technicians, and metalworkers drilling steel, stainless, titanium, and other hard alloys.

Key Features

• Cobalt tool material for heat and wear resistance in hard metals and abrasive alloys
• 135-degree split point with web thinning for self-centering entry and reduced thrust
• 6-inch overall length for extended reach into deep or obstructed workpieces
• Straw finish indicating cobalt-grade heat treatment
• Right-hand spiral flute with tapered web for consistent chip clearance
• Conforms to NAS 907 Type J standard for aircraft-quality drill geometry

Compatibility

Designed as an OEM-style replacement or direct-fit option for applications specifying a wire gauge No. 42 cobalt aircraft extension drill with a 0.0935-inch diameter and straight-cylindrical shank conforming to NAS 907 Type J.

Installation Notes

This bit is installed by machinists and aviation maintenance technicians using standard drill chucks compatible with a 0.0935-inch straight-cylindrical shank. Secure the workpiece firmly before drilling and use appropriate cutting fluid or lubricant when working with hard alloys to extend tool life. Do not exceed the recommended feed rate or spindle speed for the material being drilled. Inspect the split point for chipping or wear before each use and replace the bit if the cutting edges are degraded.