Precision Twist Drill 5999686 Cobalt Jobber Drill 1.85mm

Product Description

The PRECISION TWIST DRILL 5999686 is a cobalt high-speed steel jobber-length drill bit designed for drilling operations in steel and other demanding workpiece materials. It measures 1.85 mm (0.0728 inches) in diameter with an overall length of 1-13/16 inches (1.8125 inches) and a flute length of 55/64 inches (0.8594 inches). The 135-degree split point reduces walking and lowers the thrust required to start a hole without a center punch. The oxide and straw finish provides mild lubricity and corrosion resistance during use. This is a general-purpose heavy-duty bit suited for production and maintenance drilling by machinists, tool-and-die technicians, and industrial maintenance trades.

This bit is built for drilling steel and compatible with workpiece material codes P, M, K, N, and S per DIN classification, covering a broad range of ferrous and non-ferrous materials. The Series 2ACO designation follows DIN 338 and ANSI standards, making it a direct fit for standard jobber-drill applications in drill presses, CNC machining centers, and hand-held power drills where a straight-shank bit is required. The 12xD flute-to-diameter ratio provides adequate chip evacuation at this small diameter. Typical applications include through-hole and blind-hole drilling in steel plate, structural components, and machined parts.

Key Features

• Cobalt construction for improved heat and wear resistance over standard HSS in steel drilling
• 135-degree web-thinned split point reduces thrust and self-centers on the workpiece
• Oxide and straw coating adds surface lubricity and mild corrosion protection
• Regular spiral flute with tapered web configuration promotes efficient chip removal
• Straight cylindrical shank at 1.85 mm (0.0728 inches) fits standard drill chucks without modification
• Meets DIN 338 and ANSI standards for consistent dimensional accuracy

Compatibility

Designed as a general-purpose jobber drill compatible with workpiece materials classified under DIN codes P (steel), M (stainless), K (cast iron), N (non-ferrous), and S (heat-resistant alloys). Fits any standard drill chuck accepting a 1.85 mm straight shank. Conforms to DIN 338 and ANSI specifications.

Installation Notes

Installation and use of this drill bit is performed by machinists, maintenance technicians, or qualified tradespeople using a drill press, hand drill, or CNC spindle with an appropriate collet or keyed chuck. Secure the workpiece firmly before drilling to prevent movement at this small diameter. At 1.85 mm, the bit is susceptible to breakage under side-loading or excessive feed pressure — use consistent, controlled feed rates and appropriate cutting fluid on steel. Inspect the cutting edges before each use and replace if chipping or dulling is observed.