Precision Twist Drill 6001393 Aircraft Extension Drill Bit

Product Description

The PRECISION TWIST DRILL 6001393 is a high speed steel aircraft extension drill bit designed for deep-reach drilling applications where standard-length bits cannot access the worksite. Built to Series 500-12 specifications, this bit measures 31/64 inch (0.4844 inch decimal) in diameter with a 4-3/8 inch flute length and a 12 inch overall length, making it the right choice for drilling through structural assemblies, aircraft frames, and deep-cavity workpieces. The 135-degree split point is self-centering, eliminating the need for a center punch on most materials. An oxide finish provides basic surface protection. Two right-hand spiral flutes clear chips efficiently during drilling operations.

This drill bit is suited for metalworking applications in aerospace, fabrication, and general manufacturing environments. The extended 12 inch overall length is specifically built for applications requiring reach beyond standard drill extensions, such as drilling through structural members, deep channels, or confined spaces on aircraft airframes and industrial assemblies. It is used by machinists, aviation maintenance technicians, and fabricators working with aluminum, mild steel, and similar materials. The straight-cylindrical shank fits standard three-jaw drill chucks without an adapter.

Key Features

• 135-degree split point with self-centering tip reduces walking and eliminates most center-punch requirements
• 12 inch overall length provides extended reach for deep-cavity and structural drilling
• High speed steel construction handles general-purpose metalworking applications
• Oxide finish adds surface protection against moisture and minor corrosion
• Tapered web with web thinning reduces thrust force and eases penetration
• Meets NAS 907 Type B standard for aircraft-quality drill bit performance

Compatibility

Designed as an OEM-style aircraft extension drill bit compatible with standard three-jaw drill chucks accepting a 31/64 inch straight-cylindrical shank. Meets NAS 907 Type B standards for use in aerospace and general metalworking applications.

Installation Notes

This bit is installed and operated by machinists, aviation maintenance technicians, and metalworking professionals using standard drill presses, magnetic drills, or hand-held electric drills with a compatible chuck. Secure the shank fully in the chuck before operation and verify the workpiece is clamped to prevent rotation. Appropriate cutting fluid or lubricant should be used when drilling steel to extend bit life and manage heat buildup. Follow applicable workplace safety standards and aviation maintenance manual procedures when working on aircraft structures.