Precision Twist Drill 5996155 Cobalt Drill Bit Wire 16

Product Description

The PRECISION TWIST DRILL 5996155 is a cobalt aircraft extension drill bit designed for demanding drilling applications in hard metals, stainless steel, and high-strength alloys. Built to Series CO501-6 standards and compliant with NAS 907 Type J, it features a 135-degree split point that is self-centering, reducing the need for a center punch and minimizing walking on entry. The straight-cylindrical shank measures 0.1770 inches in diameter, matching the wire size 16 drill diameter. A straw finish indicates the cobalt steel has been heat-treated, providing added hardness and wear resistance for extended tool life in tough materials.

This drill bit is suited for aerospace, automotive, and industrial maintenance applications where extended reach is needed. The 6-inch overall length with a 2.1875-inch spiral flute provides the additional clearance required when drilling through thick stock, deep holes, or recessed locations that standard-length bits cannot reach. It is typically used by maintenance machinists, aircraft maintenance technicians, and metal fabricators working in production or field repair environments. The right-hand cutting direction and two-flute spiral design promote efficient chip evacuation throughout the cut.

Key Features

• 135-degree split point with self-centering geometry reduces walking and eliminates the need for a center punch
• Cobalt tool material provides superior heat and wear resistance compared to standard high-speed steel
• Extended 6-inch overall length with 2.1875-inch flute length delivers reach for deep or recessed drilling
• Straw finish indicates heat treatment for improved hardness and longevity
• Web-thinned, tapered web configuration reduces thrust force during penetration
• NAS 907 Type J compliant for aerospace-grade dimensional and performance standards

Compatibility

Designed as a general-purpose aircraft extension drill bit in Series CO501-6, suited for use in standard drill chucks accepting a 0.1770-inch straight-cylindrical shank across portable drills, drill presses, and magnetic-base drills.

Installation Notes

Installation and use of this drill bit should be performed by qualified machinists or maintenance technicians familiar with metal cutting operations. Secure the shank fully in the drill chuck and verify runout before beginning the cut. Use appropriate cutting fluid for the workpiece material to manage heat buildup, particularly when drilling stainless steel or high-strength alloys. Wear proper eye protection and secure the workpiece to prevent rotation during drilling.