Precision Twist Drill 6001351 Letter Z Aircraft Extension Drill

Product Description

The PRECISION TWIST DRILL 6001351 is a Letter Z aircraft extension drill bit designed for deep-hole drilling applications where standard-length bits cannot reach. Built from high speed steel with an oxide finish, this bit features a 135-degree split point that is self-centering and eliminates the need for a center punch on most materials. The straight-cylindrical shank measures 0.413 inches in diameter, matching the bit diameter for secure chuck engagement. With a flute length of 3.875 inches and an overall length of 6 inches, it delivers the reach required in aircraft, sheet metal, and structural fabrication work. Web thinning reduces thrust and improves chip evacuation in demanding cuts.

This drill bit is suited for use in aviation maintenance, aerospace fabrication, and general metalworking applications where extended reach is required. It is commonly used by aircraft mechanics, precision machinists, and metalworking tradespeople drilling through structural members, bulkheads, or stacked materials where a standard jobber-length bit falls short. The Series 502-6 designation places it within a recognized line of extension-length HSS drill bits built to NAS 907 Type B standards.

Key Features

• 135-degree split point is self-centering, reducing drill walk on metal surfaces
• High speed steel construction handles steel, aluminum, and general-purpose metalworking applications
• Oxide finish improves lubricity and provides mild corrosion resistance during storage and use
• Extended 6-inch overall length with 3.875-inch flute length provides reach beyond standard jobber bits
• Web-thinned tapered web reduces cutting resistance and improves chip flow
• Right-hand spiral flute with 2-flute configuration for efficient chip removal

Compatibility

Designed as an OEM-style replacement and standard-stock drill bit for use in 3/8-inch or larger keyed and keyless drill chucks accepting a 0.413-inch straight-cylindrical shank. Conforms to NAS 907 Type B standards.

Installation Notes

This drill bit is installed and used by machinists, aircraft mechanics, and metalworking tradespeople. Secure the straight-cylindrical shank fully in the chuck before drilling and confirm the chuck is properly tightened. Use appropriate cutting fluid for steel or hard alloys to extend bit life and reduce heat buildup. Inspect the cutting edges and split point for wear or chipping before each use, as a damaged point reduces accuracy and increases the risk of bit breakage.