Precision Twist Drill 5997819 Cobalt Jobber Drill Bit

Product Description

The PRECISION TWIST DRILL 5997819 is a wire-gauge cobalt jobber drill bit designed for drilling operations in ferrous and non-ferrous metals, stainless steel, and other demanding workpiece materials. It carries a 0.0250 inch (wire size 72) diameter with a 135-degree split point for fast, self-centering starts that reduce walking on hardened or smooth surfaces. The straw oxide finish improves lubricity and surface hardness. With a 2-flute regular spiral configuration and web-thinned, tapered web design, this bit clears chips efficiently in short-hole drilling applications. It meets ANSI and NAS 907 standards and is rated as a heavy-duty general-purpose tool.

This bit is suited for production and maintenance drilling in steel, cast iron, aluminum, and similar materials where tight hole tolerances and consistent performance are required. The straight cylindrical shank fits standard drill chucks without adapters, making it practical for hand-held drills, drill presses, and CNC setups. It is well matched for precision work in aerospace, tooling, and general metalworking environments where wire-gauge sizing is specified. Licensed machinists, tool-and-die technicians, and maintenance mechanics are the primary installers and users of this drill bit series.

Key Features

• Cobalt high-speed steel construction for heat and wear resistance in hard metals
• 135-degree split point reduces thrust and provides self-centering starts without a center punch
• Straw oxide finish improves lubricity and extends tool life in steel drilling
• Web-thinned, tapered web reduces cutting resistance and improves chip evacuation
• Right-hand, regular spiral flute for standard drill chuck compatibility
• Meets ANSI and NAS 907 standards for heavy-duty general-purpose drilling

Compatibility

Part of the R10CO-R15CO-R18CO series. Designed for use in ferrous metals, cast iron, aluminum, and similar workpiece materials as designated by primary workpiece material codes P, M, K, N, and S. Fits any standard drill chuck accepting a 0.0250 inch straight cylindrical shank.

Installation Notes

Install and remove this bit only after the drill or machine spindle is fully powered down and locked out per applicable OSHA lockout/tagout procedures. Secure the straight shank firmly in the chuck to prevent slippage during drilling. Use appropriate cutting fluid or coolant for steel and hard-metal applications to maintain edge life. Inspect the cutting edges and web before each use and replace if chipping or excessive wear is present.