Precision Twist Drill 5996113 Cobalt Extension Drill Bit 48

Product Description

The PRECISION TWIST DRILL 5996113 is a cobalt aircraft extension drill bit designed for drilling in hard metals, stainless steel, and high-strength alloys where standard high-speed steel bits fall short. Wire size 48 (0.076 inches decimal), this bit features a 135-degree split point for self-centering entry without a center punch. The 6-inch overall length provides extended reach in deep-cavity or obstructed-access drilling applications. A straw finish indicates heat treatment consistent with cobalt tooling. Right-hand spiral flutes with a 2-flute configuration clear chips efficiently during drilling. Intended for use by machinists, aerospace technicians, maintenance mechanics, and skilled tradespeople working in ferrous and exotic materials.

This bit is well suited for aircraft maintenance, structural metalwork, and precision drilling in tight or recessed locations where standard-length bits cannot reach. The extended 6-inch overall length with a 1-inch flute length keeps the cutting zone short and rigid while the shank provides the necessary reach. General-purpose cobalt construction makes it appropriate for production drilling, repair work, and field maintenance on metal structures, frames, and assemblies. The Series CO501-6 designation identifies this as part of a standardized cobalt extension drill family conforming to NAS 907 Type J standards.

Key Features

• 135-degree split point for self-centering starts without a center punch
• Cobalt tool material for durability in hard metals and stainless steel
• 6-inch overall length for extended reach in obstructed or deep locations
• Straight-cylindrical shank (0.076 inches) fits standard drill chucks
• 2-flute right-hand spiral with tapered web and web-thinned geometry for efficient chip clearance
• Straw finish consistent with cobalt heat treatment process
• Meets NAS 907 Type J standard

Compatibility

Designed as an OEM-style general-purpose cobalt extension drill conforming to NAS 907 Type J; fits any standard drill chuck or collet accepting a 0.076-inch straight-cylindrical shank.

Installation Notes

Installation of this bit is performed by machinists or qualified tradespeople using a drill press, hand drill, or pneumatic drill motor with a compatible chuck. Secure the shank fully in the chuck before use to prevent runout or slippage. Use appropriate cutting fluid or lubricant when drilling hard metals to preserve bit life and reduce heat buildup. Wear appropriate PPE including eye protection any time this bit is in operation.