Precision Twist Drill 5997733 Cobalt Jobber Drill Bit

Product Description

The PRECISION TWIST DRILL 5997733 is a wire size No. 3 cobalt jobber-length drill bit designed for general-purpose and heavy-duty drilling applications in ferrous and non-ferrous metals. The bit measures 0.2130 inches in diameter with a 135-degree split point that reduces walking and improves hole entry without a center punch. The oxide and bronze straw coating provides lubricity and mild heat resistance during cutting. At 3.75 inches overall length with a 2.5-inch flute length, this bit is built to NAS 907 and ANSI standards and is suited for use in drill presses, CNC machines, and hand-held power drills.

This jobber drill is intended for drilling steel and a broad range of workpiece material codes including P, M, K, N, and S classifications, covering carbon steels, stainless steels, cast irons, non-ferrous metals, and heat-resistant alloys. It is part of the R10CO-R15CO-R18CO series, which is engineered for heavy-duty production and maintenance drilling environments. The straight cylindrical shank fits standard drill chucks without adapters. Machinists, millwrights, and maintenance technicians working in fabrication, manufacturing, and field repair commonly reach for this bit.

Key Features

• Cobalt high-speed steel construction for elevated heat and wear resistance in tough metals
• 135-degree web-thinned split point reduces thrust and eliminates drill walk on entry
• Oxide and bronze straw coating adds lubricity and extends tool life in steel drilling
• Regular spiral flute geometry with tapered web for efficient chip evacuation
• Straight cylindrical shank fits standard 3-jaw drill chucks without adapters
• Meets NAS 907 and ANSI standards for heavy-duty drill bit performance

Compatibility

Part of the PRECISION TWIST DRILL R10CO-R15CO-R18CO series. Compatible with standard drill chucks accepting a 0.2130-inch straight shank. Suited for drilling steel, stainless steel, cast iron, non-ferrous metals, and heat-resistant alloys per material codes P, M, K, N, and S.

Installation Notes

Machinists and maintenance technicians should secure the workpiece fully before drilling and ensure the chuck is tightened on the straight shank with no runout. Appropriate cutting fluid or coolant is recommended when drilling hardened or stainless steels to manage heat buildup, particularly at the maximum 2.5-inch drilling depth. Inspect the cutting edges for wear regularly, as cobalt bits used beyond their service life can fracture under load. Follow shop safety practices and machine-specific RPM recommendations for the workpiece material.