Precision Twist Drill 5995992 Cobalt Drill Bit Wire 2

Product Description

The PRECISION TWIST DRILL 5995992 is a high-performance cobalt aircraft extension drill bit designed for demanding metal drilling applications. Built to Series CO501-6 standards and compliant with NAS 907 Type J, this bit features a 135-degree split point with self-centering geometry and web-thinned, tapered web construction for fast, accurate starts without a center punch. The 0.221-inch diameter straight-cylindrical shank keeps the bit concentric in standard chucks and extension holders. A straw finish indicates cobalt heat treatment, supporting durability in high-heat, high-speed drilling into hardened steel, stainless, and aerospace-grade alloys. Two right-hand spiral flutes with a 2.625-inch flute length provide efficient chip evacuation through deep holes.

This extension drill bit is suited for aerospace, industrial, and heavy fabrication work where standard-length bits cannot reach. The extended 6-inch overall length makes it practical for drilling in recessed locations, structural assemblies, and tight access areas encountered in aircraft maintenance, shipbuilding, and industrial manufacturing. Wire size 2 (0.221 inches) is a common specification for close-tolerance fastener holes in metal fabrication and structural drilling applications. Licensed HVAC, mechanical, and industrial tradespeople performing sheet metal or equipment frame work will also find this size useful for precise hole placement.

Key Features

• 135-degree split point with self-centering geometry eliminates the need for a center punch on most metals
• Cobalt tool material with straw finish for heat resistance and extended tool life in hard metals
• Web-thinned, tapered web reduces thrust and improves penetration in tough materials
• 6-inch overall length with 2.625-inch flute length for deep-reach drilling applications
• Right-hand spiral flutes promote efficient chip clearing in blind and deep holes
• Compliant with NAS 907 Type J for aerospace and high-specification industrial use

Compatibility

Designed as a direct-fit replacement or supplemental drill bit for applications requiring wire size 2 (0.221-inch diameter) cobalt extension drills conforming to NAS 907 Type J specifications in Series CO501-6.

Installation Notes

This drill bit is intended for use by trained machinists, metalworkers, and maintenance tradespeople operating drill presses, magnetic base drills, or handheld electric drills with appropriate chuck capacity. Secure the straight-cylindrical shank firmly in a correctly sized chuck or extension holder before operation. Use cutting fluid appropriate for the base material to reduce heat buildup and extend bit life. Do not exceed the recommended RPM range for the material and bit diameter being drilled.