Precision Twist Drill 5999908 Reduced Shank Drill Bit

Product Description

The PRECISION TWIST DRILL 5999908 is a reduced shank twist drill bit designed for general-purpose drilling in ferrous metals and a wide range of secondary materials. The bit measures 1.375 inches in diameter with a 0.500-inch straight-cylindrical shank, allowing it to chuck into standard 1/2-inch drill chucks despite the larger cutting diameter. The 118-degree standard point angle is suited for drilling steel, aluminum, copper, and similar materials. Constructed from high speed steel with a bright uncoated finish, this Series R56 bit offers reliable performance across common shop and field drilling tasks. Total weight is 0.5 pounds.

This drill bit fits applications in mechanical, HVAC, plumbing, and electrical trade work where large-diameter holes are needed in ferrous metal, aluminum, copper, magnesium, nickel, titanium, and synthetic materials. The reduced shank design extends compatibility to standard 1/2-inch chucks while the 3-inch flute length and 6-inch overall length give adequate reach for most structural and panel drilling situations. It is suited for right-hand rotation drills in both bench-press and handheld configurations for general production and maintenance use.

Key Features

• 1.375-inch cutting diameter with 0.500-inch reduced straight-cylindrical shank for use in standard 1/2-inch chucks
• 118-degree standard point angle for general-purpose performance in ferrous and non-ferrous materials
• High speed steel construction provides durability across a broad range of workpiece materials
• Bright uncoated finish — no coating buildup to affect tolerance on precision holes
• 3-inch flute length with regular spiral for efficient chip evacuation
• 6-inch overall length suits standard drilling depths in structural and panel applications

Compatibility

Designed as an OEM-style replacement and general-use reduced shank drill bit compatible with 1/2-inch chuck capacity drills and drill presses. Rated for use in ferrous metal, aluminum, cermet, copper, magnesium, nickel, synthetic, and titanium workpiece materials per Series R56 application data.

Installation Notes

Installation is performed by machinists, maintenance technicians, and trade professionals using standard 1/2-inch keyed or keyless drill chucks. Secure the shank fully into the chuck before drilling and verify chuck tightness to prevent slippage on large-diameter cuts. Use appropriate cutting fluid or coolant for extended run times in hard ferrous metals, though the bit is rated for dry cutting in general applications. Follow applicable shop safety practices including eye protection and secure workpiece fixturing before operation.