Precision Twist Drill 5996083 Cobalt Aircraft Extension Drill

Product Description

The PRECISION TWIST DRILL 5996083 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 fall short. Sized at wire gauge number 4 (0.209 inches decimal), this bit features a 135-degree split point for self-centering entry without a center punch. The straw finish indicates cobalt content throughout the tool, not just a surface coating. With a 2.5-inch flute length and 6-inch overall length, it reaches into recessed locations that standard-length drills cannot access. Two spiral flutes with a web-thinned, tapered web configuration support chip evacuation in deeper cuts. Series CO501-6 from Precision Twist Drill.

This drill bit is suited for aerospace, automotive, and industrial maintenance applications where extension reach and material hardness demand a cobalt tool. The 6-inch overall length makes it useful for drilling through structural members, frames, or assemblies where a jobber-length bit cannot reach. Right-hand cutting direction is standard for conventional drill press and hand drill use. General-purpose performance classification means it handles a broad range of ferrous and non-ferrous materials. Machinists, aircraft maintenance technicians, and industrial maintenance mechanics are the primary installers of this type of tooling. Complies with NAS 907 Type J standards.

Key Features

• Cobalt construction with straw finish for drilling hard metals and stainless steel
• 135-degree split point is self-centering, eliminating the need for a center punch in most applications
• 6-inch overall length provides extension reach into recessed or deep structural locations
• Web-thinned tapered web reduces cutting resistance and improves chip clearance
• Two spiral flutes with right-hand cutting direction for use in standard drill presses and hand drills
• Meets NAS 907 Type J standard for aircraft-quality drilling

Compatibility

Designed as an OEM-style general-purpose cobalt aircraft extension drill for use in standard straight-shank drill chucks compatible with a 0.209-inch shank diameter.

Installation Notes

This bit is installed by machinists and aircraft or industrial maintenance technicians using standard drill presses, magnetic-base drills, or hand drills with a compatible chuck. Secure the workpiece before drilling and use appropriate cutting fluid when drilling hard metals to extend bit life and reduce heat buildup. Do not exceed the drill speed recommendations for cobalt bits in the material being drilled. Wear appropriate PPE including eye protection during all drilling operations.