Precision Twist Drill 5999739 Taper Length Drill Bit

Product Description

The PRECISION TWIST DRILL 5999739 is a taper length drill bit designed for general-purpose drilling across a broad range of materials in trade and industrial applications. Manufactured from high speed steel with a bright/uncoated finish, it carries a 118-degree standard point angle and a web-thinned, tapered web configuration that reduces entry force and improves chip clearance. The bit measures 25/64 inch (0.3906 inches) in diameter with a 7-inch overall length and a 4-3/8-inch spiral flute. The straight shank matches the drill bit diameter, making it compatible with standard chucks. This is a right-hand cut, regular spiral bit suited for machinists, maintenance technicians, and trade professionals who need reliable performance in production or field drilling setups.

The 5999739 is built for use on a wide range of workpiece materials including alloy steel, carbon steel, stainless steel, cast iron, malleable iron, aluminum, aluminum alloy, brass, bronze, high strength bronze, copper, magnesium, magnesium alloy, nickel, nickel alloy, reinforced plastics, graphite, cermet, and hardened steel. The taper length body gives it greater reach than a jobber bit without sacrificing rigidity, making it well suited for deep-hole drilling in structural components, fabrication shops, and on-site mechanical work where a standard length bit falls short.

Key Features

• 25/64 inch (0.3906 inches) diameter with matching straight shank for secure chuck engagement
• 118-degree standard point angle with web-thinned, tapered web for reduced thrust and cleaner entry
• High speed steel construction for general-purpose durability across ferrous and non-ferrous materials
• 4-3/8-inch spiral flute length at a 6xD flute-to-diameter ratio for efficient chip evacuation
• Bright/uncoated finish suitable for use with cutting fluids or dry drilling
• Right-hand cut, regular spiral flute — Series R51, ANSI standard

Compatibility

Designed as a general-purpose taper length drill bit compatible with standard drill chucks accepting straight shank tooling at 25/64 inch shank diameter. Suitable for use in drill presses, lathes, and hand-held drilling equipment where straight shank taper length bits are specified.

Installation Notes

Install in a properly rated chuck and verify shank seating before operation. Power down and de-energize the drilling equipment before changing bits. Use appropriate cutting fluid for the workpiece material when drilling ferrous metals or stainless steel to extend tool life and control heat. Inspect the cutting edges for wear or chipping before each use and replace if the point geometry is compromised.