Precision Twist Drill 5996021 No. 27 Cobalt Drill Bit

Product Description

The PRECISION TWIST DRILL 5996021 is a screw machine length cobalt drill bit sized to No. 27 wire gauge, equivalent to 0.1440 inch diameter. Designed for high-performance drilling in hard materials, it features a 135-degree split point that reduces walking and requires no center punch in most applications. The web-thinned, tapered web construction lowers thrust requirements and improves chip evacuation. At 2-1/16 inches overall length, this short-length geometry provides added rigidity in screw machine, CNC, and drill press applications. M41 cobalt construction delivers heat and wear resistance well beyond standard high-speed steel bits. The straight-cylindrical shank seats securely in standard drill chucks.

This bit is suited for machinists, toolroom technicians, and industrial maintenance professionals drilling hard ferrous metals, stainless steel, hardened alloys, and other tough workpiece materials. The screw machine length is standard in production environments where shorter flute length and overall length improve stability and reduce deflection. A 1-inch flute length and 2.5xD flute-to-diameter ratio support controlled chip flow in blind and through-hole operations. Right-hand cutting direction is compatible with standard right-hand spindle rotation on lathes, drill presses, and CNC machining centers.

Key Features

• No. 27 wire size, 0.1440 inch diameter with matching 0.1440 inch straight-cylindrical shank
• 135-degree split point reduces bit walking and lowers entry thrust
• M41 cobalt construction for heat resistance in hard and abrasive materials
• Web-thinned tapered web promotes efficient chip evacuation
• Screw machine length at 2-1/16 inches OAL for rigidity in production setups
• Meets ANSI standards; right-hand cut with regular spiral fluting

Compatibility

Designed as an OEM-style replacement or direct-fit screw machine drill bit for use in standard drill chucks accepting a 0.1440 inch straight-cylindrical shank, compatible with drill presses, lathes, and CNC machining centers running right-hand spindle rotation.

Installation Notes

Installation and use should be performed by qualified machinists or toolroom technicians familiar with rotating cutting tools. Ensure the machine spindle is fully stopped and power is isolated before inserting or removing the bit from the chuck. Confirm chuck jaws are tightened evenly and the shank is fully seated before operation. Always follow applicable shop safety standards and machine manufacturer guidelines for feed rate and spindle speed selection when drilling hard materials.