Precision Twist Drill 5999664 Taper Length Drill Bit

Product Description

The PRECISION TWIST DRILL 5999664 is a taper length, high speed steel drill bit designed for general-purpose drilling across a wide range of metals and materials. It features a 0.2500-inch (1/4 inch) diameter, a 118-degree standard point angle, and a bright/uncoated finish suited for dry or lightly lubricated drilling applications. The spiral flute geometry and web-thinned, tapered web design promote efficient chip evacuation and reduced thrust during entry. At 6.125 inches in overall length with a 3.75-inch flute, this bit provides the extended reach needed for deeper hole applications while maintaining rigidity. It is installed by machinists, maintenance mechanics, and fabricators working in shop and field environments.

This bit is appropriate for residential and commercial fabrication, maintenance, and repair operations. The Series R51 taper length configuration suits applications where standard jobber-length bits fall short. Compatible materials include alloy steel, aluminum, aluminum alloy, brass, bronze, carbon steel, cast iron, copper, graphite, hardened steel, high strength bronze, magnesium, magnesium alloy, malleable iron, nickel, nickel alloy, reinforced plastic materials, and stainless steel. Right-hand cutting direction is standard for conventional drill press, hand drill, and mill spindle use.

Key Features

• 0.2500-inch diameter, also designated as drill size E (letter) and 1/4 inch (fractional)
• 118-degree standard point angle with web-thinned, tapered web for reduced thrust and easier starts
• High speed steel construction for general-purpose performance across a broad material range
• Bright/uncoated finish — compatible with a wide range of cutting fluids
• 3.75-inch flute length with regular spiral for efficient chip clearing in deeper holes
• Straight, non-threaded 0.2500-inch shank fits standard drill chucks and collets
• Meets ANSI standards for dimensional accuracy and interchangeability

Compatibility

Designed as a general-purpose taper length drill bit suitable for use in standard drill presses, hand drills, CNC machining centers, and milling machines accepting a 0.2500-inch straight shank. Compatible with alloy steel, aluminum, brass, bronze, carbon steel, cast iron, copper, stainless steel, nickel alloys, magnesium alloys, and reinforced plastic materials as specified by the manufacturer.

Installation Notes

Install in a properly sized chuck or collet and verify shank is fully seated and secured before operation. Power down and de-energize or lock out the machine before changing bits. Use appropriate cutting fluid for the workpiece material to extend bit life and improve finish quality. Inspect the cutting edges and web for wear or damage before each use and replace when point geometry is no longer within spec.