Precision Twist Drill 5999851 Extra Length Drill Bit

Product Description

The PRECISION TWIST DRILL 5999851 is a high speed steel extra length drill bit designed for deep-hole drilling applications where standard-length bits fall short. With a 3/16 inch (0.1875 inch) diameter and an overall length of 15 inches, this bit reaches into deep cavities, long-run bores, and hard-to-access workpiece features that shorter tooling cannot reach. The 11-inch spiral flute length promotes efficient chip evacuation over extended depths, and the web-thinned, tapered-web tip geometry reduces thrust and improves centering at entry. The 118-degree standard point angle suits general-purpose drilling in a wide range of materials. Installed by machinists and metalworking professionals using standard drill presses, mill spindles, or handheld drills with appropriate speed and feed control.

This bit is suited for drilling aluminum, magnesium, copper, nickel, titanium, synthetic materials, and a range of secondary workpiece materials including stainless steel, nickel alloys, malleable iron, hardened steel, high strength bronze, magnesium alloy, and reinforced plastics. The extra length makes it particularly useful in fixture work, structural fabrication, and deep-bore production environments where reach and chip clearance are critical. Right-hand cutting direction with regular spiral geometry keeps the bit compatible with standard right-hand spindle equipment.

Key Features

• 15-inch overall length for deep-hole and hard-to-reach drilling applications
• 11-inch flute length supports chip evacuation over extended bore depths
• 118-degree standard point angle for general-purpose entry and centering
• Web-thinned, tapered-web construction reduces cutting thrust and improves tip stability
• High speed steel construction, uncoated, for use across a broad material range
• Straight-cylindrical shank compatible with standard drill chucks and collets
• 2-flute, right-hand spiral geometry for conventional right-hand spindle use

Compatibility

Designed as a general-purpose extra length drill bit conforming to ANSI standards, Series 1511, compatible with any drill press, milling machine spindle, or handheld drill accepting a 3/16 inch straight-cylindrical shank. Suitable for primary workpiece materials including aluminum, magnesium, copper, nickel, synthetic, and titanium, as well as secondary materials such as stainless steel, hardened steel, nickel alloy, malleable iron, high strength bronze, magnesium alloy, and reinforced plastics.

Installation Notes

Install and secure the straight-cylindrical shank firmly in the chuck or collet before operating. Apply appropriate cutting fluid or lubricant for the workpiece material to extend tool life and improve hole finish, particularly in stainless steel and nickel alloys. Reduce spindle speed relative to standard-length bits of the same diameter to account for the extended reach and increased deflection risk. Periodically retract the bit to clear chips and prevent packing in deep-hole operations.