Precision Twist Drill 5997883 No. 48 Cobalt Jobber Drill

Product Description

The PRECISION TWIST DRILL 5997883 is a No. 48 wire-gauge cobalt jobber-length drill bit designed for general-purpose and heavy-duty drilling in steel and other demanding workpiece materials. Built from cobalt high-speed steel with a straw oxide finish, it runs a 135-degree split point that reduces walking on entry and cuts through harder stock without requiring a center punch. The straight cylindrical shank measures 0.076 inches in diameter, matching the No. 48 wire size, and the overall length is 2 inches. With a web-thinned, tapered-web design and regular spiral fluting, this bit is built for consistent chip evacuation and extended tool life in production and maintenance drilling applications.

This drill bit is suited for drilling steel, cast iron, non-ferrous metals, and composites in residential, commercial, and industrial settings. The cobalt construction makes it a practical choice for harder alloys and stainless steel where standard high-speed steel bits wear prematurely. Typical install scenarios include HVAC techs drilling sheet metal for fasteners or brackets, plumbers drilling through hangers and strapping, and electricians drilling metal panels and enclosures. It is sold individually but must be ordered in multiples of 12 per the manufacturer minimum order requirement.

Key Features

• No. 48 wire size with 0.076-inch decimal diameter for precise, tight-tolerance hole sizing
• Cobalt high-speed steel construction provides superior heat and wear resistance over standard HSS
• 135-degree split point reduces thrust, minimizes bit walking, and improves hole entry accuracy
• Straw oxide finish adds lubricity and corrosion resistance for extended service life
• Web-thinned, tapered-web design promotes efficient chip clearing and reduces cutting resistance
• Meets ANSI and NAS 907 standards for dimensional accuracy and material performance

Compatibility

Part of the R10CO-R15CO-R18CO series. Designed for use in standard drill chucks and drill presses accepting straight cylindrical shanks with a 0.076-inch shank diameter. Compatible primary workpiece material codes include P, M, K, N, and S per ISO classification, covering steel, stainless, cast iron, non-ferrous, and high-temperature alloys.

Installation Notes

Installation and use of this drill bit is appropriate for licensed tradespeople and experienced machinists. Ensure the drill chuck is clean and the bit is seated fully and centered before tightening. Use cutting fluid when drilling harder steels or stainless to reduce heat buildup and extend bit life. Do not exceed recommended drilling depth of 1 inch for this bit size.