Precision Twist Drill 5997879 Cobalt Jobber Drill No. 47

Product Description

The PRECISION TWIST DRILL 5997879 is a No. 47 wire-gauge cobalt jobber-length drill bit designed for drilling into steel and other demanding workpiece materials. It features a 135-degree split point that self-centers on contact, reducing walking and eliminating the need for a center punch on most surfaces. The bit measures 2 inches overall length with a 1-inch flute length and carries an oxide-bronze straw coating that improves lubricity and surface hardness. With a straight cylindrical shank and two regular spiral flutes, this bit is intended for use in standard drill chucks by machinists, maintenance mechanics, and metalworking tradespeople working on production or repair tasks.

This drill bit is suited for general-purpose drilling in steel, stainless steel, cast iron, non-ferrous metals, and high-temperature alloys, consistent with workpiece material codes P, M, K, N, and S. It is sized at 5/64 inch (0.0781 inch decimal), making it appropriate for tapping pilot holes, close-tolerance fastener clearance holes, and similar precision drilling operations. The web-thinned, tapered-web construction reduces thrust requirements and improves chip evacuation at the cutting edge. It conforms to ANSI standards and NAS 907 specification.

Key Features

• 135-degree split point for self-centering and reduced thrust
• Cobalt high-speed steel construction for heavy-duty cutting performance in ferrous and high-temp alloys
• Oxide-bronze straw coating for improved lubricity and wear resistance
• Web-thinned, tapered-web design improves chip clearance and reduces heat buildup
• Right-hand cutting with regular spiral flutes for standard drill chuck use
• Meets ANSI and NAS 907 specifications

Compatibility

Designed as a general-purpose jobber drill bit compatible with standard straight-shank drill chucks; part of the R10CO-R15CO-R18CO series.

Installation Notes

Installation should be performed by a qualified machinist or metalworking technician using a properly rated drill press, hand drill, or CNC drilling machine. Ensure the drill chuck is securely tightened and the shank is fully seated before operation. Use appropriate cutting fluid or coolant to extend tool life when drilling ferrous materials at sustained depths. Inspect the cutting edge before use and replace any bit showing chipping or excessive wear.