Precision Twist Drill 5996094 Cobalt Aircraft Drill Bit 43

Product Description

The PRECISION TWIST DRILL 5996094 is a cobalt aircraft extension drill bit designed for demanding drilling applications in hard and abrasive materials. Built to Series CO501-6 specifications, it carries a wire gauge size of 43, which corresponds to a decimal diameter of 0.089 inches, and features a 135-degree split point for self-centering entry without a center punch. The straw finish indicates controlled heat treatment, and the two-flute spiral geometry with a web-thinned, tapered web configuration promotes efficient chip evacuation. This bit is sold individually and is suited for use by machinists, aircraft maintenance technicians, and industrial tradespeople who require precision in tight-tolerance applications.

This drill bit is built for general-purpose drilling in metals, alloys, and composite materials where cobalt tooling is preferred over standard high-speed steel. The 6-inch overall length provides extended reach into recessed or obstructed workpieces, making it well-suited for aircraft structural work, sheet metal fabrication, and industrial maintenance tasks. The straight-cylindrical shank is compatible with standard drill chucks, and the right-hand cutting direction is consistent with conventional drill press and handheld power tool operation. The 1.25-inch flute length delivers a 4xD length-to-diameter ratio appropriate for moderate-depth holes.

Key Features

• Wire size 43 with 0.089-inch decimal diameter for precision hole sizing
• 135-degree split point geometry for self-centering starts on flat or curved surfaces
• Cobalt tool material resists heat and wear in hard metals and stainless alloys
• Straw finish indicates tempered cobalt construction for extended tool life
• 6-inch overall length provides extended reach for aircraft and structural applications
• Web-thinned tapered web reduces thrust and improves chip flow
• Conforms to NAS 907 Type J standards for aircraft-grade tooling

Compatibility

Designed as an OEM-style aircraft extension drill bit conforming to NAS 907 Type J standards, suitable for use in standard drill chucks accepting a 0.089-inch straight-cylindrical shank across drill press, CNC, and handheld power tool setups.

Installation Notes

This drill bit is installed and operated by machinists, aircraft maintenance technicians, and industrial mechanics using standard drill chucks or collet holders. Ensure the shank is fully seated and securely clamped before operation, and verify spindle speed is appropriate for the workpiece material and bit diameter. Use cutting fluid or coolant when drilling hard metals to preserve cobalt tool life. Inspect the cutting edges before each use and replace the bit if chipping or excessive wear is observed.