Precision Twist Drill 5999655 Reduced Shank Drill Bit

Product Description

The PRECISION TWIST DRILL 5999655 is a reduced shank twist drill bit designed for general-purpose drilling in metal fabrication and industrial maintenance applications. It features a 25/32-inch (0.7812 inch decimal) cutting diameter with a 1/2-inch Weldon flat shank, allowing it to seat securely in standard 1/2-inch chuck tooling without slippage. The 118-degree standard point angle suits a broad range of ferrous and non-ferrous materials. Manufactured from high-speed steel with a bright uncoated finish, this bit delivers solid performance in production and job-site environments where a reduced shank profile is required to fit smaller chuck capacities.

This drill bit is suited for use on ferrous metals as the primary workpiece material, with secondary capability in aluminum, copper, magnesium, nickel, titanium, synthetic materials, and cermet. The Series R57 designation covers general-purpose reduced shank drilling in both shop and field settings. Machinists, maintenance technicians, and metalworking tradespeople will find this bit useful for through-hole and clearance-hole drilling where a standard-length tool is appropriate. The 3-inch flute length supports a maximum drilling depth of 3 inches, and the 4xD flute-to-diameter ratio supports efficient chip evacuation during moderate-feed drilling.

Key Features

• 25/32-inch cutting diameter (0.7812 inch decimal) with a reduced 1/2-inch Weldon flat shank for use in standard 1/2-inch chucks
• 118-degree standard point angle for general-purpose drilling in ferrous and non-ferrous metals
• High-speed steel construction with bright uncoated finish for broad material compatibility
• 3-inch flute length and 6-inch overall length with a maximum drilling depth of 3 inches
• Right-hand cut with regular spiral flute geometry for consistent chip removal
• Three Weldon flats on shank prevent bit rotation under torque load in set-screw holders

Compatibility

Designed as a general-purpose reduced shank drill bit compatible with 1/2-inch chuck tooling and Weldon-style set-screw holders. Suitable for drilling ferrous metals, aluminum, copper, magnesium, nickel, titanium, synthetic materials, and cermet. Meets ANSI standards for twist drill geometry.

Installation Notes

Installation and use of this drill bit should be performed by qualified machinists or tradespeople familiar with rotating cutting tools and applicable ANSI safety standards. Ensure the Weldon flat is fully engaged with the set screw in the holder before beginning any drilling operation. Inspect the cutting edges and shank for damage before each use, and do not exceed the recommended maximum drilling depth of 3 inches. Eye protection and appropriate workholding are required whenever this tool is in operation.