Precision Twist Drill 5999540 Reduced Shank Drill Bit

Product Description

The PRECISION TWIST DRILL 5999540 is a reduced shank drill bit designed for drilling through ferrous metals and a range of secondary materials in professional trade and industrial applications. Built from high speed steel (HSS) with a bright, uncoated finish, this bit features a 1-1/16 inch cutting diameter paired with a 1/2 inch Weldon shank, allowing it to mount in standard 1/2 inch chucks and holders without requiring a larger chuck capacity. The 118-degree standard point angle makes it well suited for general-purpose drilling in production and maintenance environments. Right-hand spiral flutes clear chips efficiently during through-hole and blind-hole operations.

This bit is sized for applications that require a larger cutting diameter than the shank diameter allows, making it a practical choice when chuck capacity is limited to 1/2 inch. It performs on ferrous metals as its primary workpiece material and is also rated for aluminum, copper, magnesium, nickel, titanium, synthetic materials, and cermet. Typical users include machinists, pipefitters, millwrights, and HVAC or plumbing technicians drilling larger clearance or access holes through structural or sheet metal components. The 6 inch overall length provides reach in deeper setups while the 3 inch flute length accommodates moderate drilling depths.

Key Features

• 1-1/16 inch cutting diameter with 1/2 inch Weldon shank for use in standard 1/2 inch holders
• High speed steel construction for durability across general-purpose metal drilling
• 118-degree standard point angle for consistent starting and penetration on flat stock
• Right-hand cut with regular spiral flutes for efficient chip evacuation
• Bright, uncoated finish suitable for use with or without cutting fluid
• 3-flat Weldon shank resists bit rotation in the holder under load
• Meets ANSI standards; Series R57

Compatibility

Designed as a general-purpose reduced shank drill bit compatible with 1/2 inch Weldon-style chucks and end mill holders. Rated for ferrous metal as the primary workpiece material, with secondary compatibility for aluminum, cermet, copper, magnesium, nickel, synthetic, and titanium materials.

Installation Notes

Installation is performed by machinists or qualified tradespeople using a 1/2 inch Weldon chuck or end mill holder; ensure the set screw engages one of the three flats on the shank before applying torque. Always power down and lock out the drilling machine before mounting or removing the bit. Secure the workpiece firmly before drilling to prevent movement, and use appropriate cutting fluid for the material type when extended run life is required.