Precision Twist Drill 5996127 Cobalt Aircraft Drill Bit

Product Description

The PRECISION TWIST DRILL 5996127 is a cobalt aircraft extension drill bit designed for drilling in hard metals, stainless steel, and high-temperature alloys where standard high-speed steel bits fail prematurely. Built to Series CO501-6 specifications, this bit features a 135-degree split point for self-centering entry without a center punch, reducing walking on curved or coated surfaces. The straw finish indicates a heat-treatment process that improves surface hardness and lubricity. At 0.067 inches in diameter (Wire Size 51) with a 1-inch flute length and 6-inch overall length, this extended-reach bit handles deep-hole applications where a standard-length bit cannot reach.

This drill bit is suited for aerospace, aviation maintenance, fabrication shops, and industrial metalworking environments requiring extended reach into confined or recessed areas. The straight-cylindrical shank fits standard drill chucks without adapters. The right-hand spiral flute and web-thinned, tapered web construction improve chip evacuation and reduce thrust force in tough materials. Machinists, aircraft mechanics, and metal fabricators working under NAS 907 Type J standards will find this bit appropriate for general-purpose drilling in difficult materials.

Key Features

• 135-degree split point is self-centering, eliminating the need for a center punch on most surfaces
• Cobalt construction provides heat resistance for drilling stainless steel, titanium, and hard alloys
• Straw finish improves surface hardness and reduces friction during cutting
• 6-inch overall length with 1-inch flute length delivers extended reach into deep or confined bores
• Web-thinned tapered web reduces cutting resistance and improves chip clearance
• Meets NAS 907 Type J standard for aircraft-quality drilling applications

Compatibility

Designed as a general-purpose aircraft extension drill bit in Series CO501-6, compatible with any standard drill chuck accepting a 0.067-inch straight-cylindrical shank.

Installation Notes

This bit is installed and used by machinists, aircraft mechanics, and metal fabricators operating drill presses, hand drills, or CNC equipment. Secure the straight-cylindrical shank firmly in the chuck before operation. Use appropriate cutting fluid when drilling hard alloys or stainless steel to extend bit life and manage heat buildup. Inspect the cutting edges for wear before each use, as cobalt bits can chip if run at incorrect speeds or feeds for the material.