Precision Twist Drill 5999869 Extra Length Drill Bit

Product Description

The PRECISION TWIST DRILL 5999869 is a 7/16-inch diameter extra length high-speed steel drill bit designed for deep-hole drilling applications in metal fabrication, maintenance, and industrial work. The 118-degree standard point angle with web thinning allows for clean penetration and reduced feed force at the start of a cut. At 15 inches overall length and an 11-inch spiral flute, this bit reaches into recessed bores and deep workpieces that standard-length drills cannot access. The bright uncoated finish and HSS construction make it suitable for a wide range of metals and synthetic materials. Machinists, pipefitters, millwrights, and industrial maintenance technicians are the primary users.

This extra length drill bit is suited for drilling through structural steel, aluminum, copper, nickel alloys, titanium, magnesium, malleable iron, stainless steel, reinforced plastics, and high-strength bronze. The 15xD flute-to-diameter ratio makes it effective in setups where standard jobber-length bits fall short, such as drilling through thick plate, long spacers, or deep fixture blocks. It operates in right-hand cutting direction and is manufactured to ANSI standards under Series 1511, a general-purpose grade for production and maintenance environments.

Key Features

• 7/16-inch diameter with matching 7/16-inch straight-cylindrical shank for positive chuck engagement
• 15-inch overall length with 11-inch flute length for deep-hole reach
• 118-degree standard point angle with web thinning and tapered web configuration for reduced thrust
• 2-flute regular spiral design promotes chip evacuation in deep bores
• Bright uncoated high-speed steel construction — no coating degradation in regrind cycles
• ANSI-compliant Series 1511 general-purpose grade

Compatibility

Designed as a general-purpose extra length drill bit for use with standard 3-jaw drill chucks, drill presses, milling machines, and hand-held power drills that accept a 7/16-inch straight-cylindrical shank. Primary workpiece materials include aluminum, magnesium, copper, nickel, synthetic, and titanium. Secondary workpiece materials include hardened steel, high-strength bronze, magnesium alloy, malleable iron, nickel alloy, reinforced plastic materials, stainless steel, and steel.

Installation Notes

Secure the shank fully in the chuck before drilling and verify runout is within acceptable limits for the application. Power down and lock out the machine before changing bits or adjusting chuck pressure. Use appropriate cutting fluid or coolant for ferrous materials to extend tool life, noting that this bit does not support through-coolant. Follow applicable shop safety standards and machine manufacturer guidelines when selecting feed rate and spindle speed for the workpiece material.