Precision Twist Drill 5997680 Cobalt Jobber Drill No 11

Product Description

The PRECISION TWIST DRILL 5997680 is a cobalt high-speed steel jobber-length drill bit sized to No. 11 wire gauge (0.1910 inches decimal). It features a 135-degree split point angle with web thinning for fast engagement and reduced walking on entry. The straw oxide finish provides added surface hardness and mild corrosion resistance. Overall length is 3.5 inches with a 2.3125-inch flute length, giving it standard jobber proportions for use in benchtop drill presses, hand drills, and CNC drilling operations. This is a general-purpose, heavy-duty bit rated for ferrous and non-ferrous materials. It is installed and used by machinists, maintenance technicians, pipefitters, and HVAC and plumbing trades needing precision hole work in metal stock.

This drill bit is suited for drilling into steel, stainless, cast iron, aluminum, and similar workpiece materials in both production and maintenance environments. The cobalt grade handles harder alloys and elevated heat better than standard HSS bits, making it a practical choice for interrupted cuts or hand-drilling into structural steel, angle iron, and pipe fittings. The straight cylindrical shank fits standard 3-jaw drill chucks across the common chuck size range. It conforms to ANSI and NAS 907 specifications, making it appropriate for aerospace and industrial maintenance applications where specification compliance is required.

Key Features

• No. 11 wire size (0.1910 inches decimal) cobalt construction for drilling harder ferrous metals
• 135-degree split point with web thinning reduces thrust and eliminates center-punch requirement on most metals
• Straw oxide finish extends surface life and provides mild lubricity during cutting
• Regular spiral flute with tapered web geometry for consistent chip evacuation
• Right-hand cutting direction, straight shank with zero flats for universal chuck compatibility
• Meets ANSI and NAS 907 standards; Series R10CO-R15CO-R18CO

Compatibility

Designed as an OEM-specification jobber drill bit conforming to ANSI and NAS 907 standards, suitable for use in any standard drill press or hand drill equipped with a 3-jaw chuck accepting a 0.1910-inch straight shank. Part of the R10CO-R15CO-R18CO series.

Installation Notes

This bit is installed by machinists, maintenance technicians, and trade professionals using standard 3-jaw keyed or keyless drill chucks. Secure the shank fully into the chuck before operation and confirm the bit runs true before cutting. Use appropriate cutting fluid or coolant when drilling hardened steels or stainless to preserve cutting edge life. Dispose of worn bits per shop safety protocols and inspect the cutting edge before each use in production applications.