Precision Twist Drill 5999667 Reduced Shank Drill Bit

Product Description

The PRECISION TWIST DRILL 5999667 is a reduced shank twist drill bit designed for general-purpose hole-making in metal fabrication and mechanical service work. The bit measures 0.75 inches in cutting diameter with a 0.5-inch Weldon flat shank, allowing it to seat securely in drill chucks and milling machine collets without slipping under torque. Built from high-speed steel (HSS) with a bright, uncoated finish, it carries a 118-degree standard point angle suited for drilling ferrous metals and a wide range of secondary materials. This is a production-grade tool installed and used by machinists, maintenance technicians, and trade professionals who require consistent, repeatable hole diameters in structural and mechanical work.

The 5999667 belongs to the PRECISION TWIST DRILL Series R57 line of reduced shank bits. The reduced shank design allows a larger-diameter bit to be chucked in a standard 1/2-inch capacity drill press, hand drill, or milling spindle without requiring a larger machine or specialized tooling. It is suited for ferrous metal stock, aluminum, copper, magnesium, nickel alloys, titanium, and synthetic materials. Typical applications include field mechanical work, shop fabrication, HVAC and plumbing rough-in for metal framing, and electrical knockout work where a clean, full-diameter hole is required.

Key Features

• Reduced shank diameter of 0.5 inches allows use in standard 1/2-inch capacity chucks despite 3/4-inch cutting diameter
• Weldon flat shank with 3 flats provides positive drive and prevents bit rotation under load
• 118-degree standard point angle for general-purpose drilling in ferrous and non-ferrous metals
• High-speed steel construction for durability across a broad range of workpiece materials
• 3-inch flute length supports drilling to a maximum depth of 3 inches in a single pass
• Right-hand spiral flute with regular helix for efficient chip evacuation

Compatibility

Designed as a general-purpose reduced shank drill bit compatible with standard 1/2-inch capacity drill chucks, drill presses, and milling machine spindles. Suitable for ferrous metal, aluminum, copper, magnesium, nickel alloys, titanium, and synthetic workpiece materials per Series R57 specifications.

Installation Notes

Secure the Weldon flat shank fully into the chuck or collet, engaging the set screw against one of the three flats to prevent rotation during use. Ensure the drill press or power tool is powered off and the chuck key is removed before inserting or removing the bit. Follow applicable shop safety standards and use appropriate cutting fluid recommendations for the workpiece material. Inspect the cutting edges for wear or chipping before each use and replace when the point shows signs of dulling to maintain hole quality and prevent workpiece damage.