Precision Twist Drill 5998207 Cobalt Jobber Drill 43/64 in

Product Description

The PRECISION TWIST DRILL 5998207 is a cobalt high-speed steel jobber-length drill bit designed for heavy-duty drilling in ferrous and non-ferrous metals. Built to NAS 907 and ANSI standards, it features a 135-degree split point that reduces walking and decreases feed pressure at the start of the cut. The straw oxide finish provides mild lubricity and helps resist heat buildup during extended drilling cycles. At 0.6719 inches in diameter with a 7.625-inch overall length, this bit is sized for production and maintenance drilling where a standard jobber reach is required. Installers and machinists use it for general-purpose hole-making in steel, stainless, cast iron, and high-temp alloys.

This drill bit is suited for metal fabrication shops, mechanical contractors, and industrial maintenance technicians working with structural steel, pipe, plate, and tube stock. The regular spiral flute and tapered web configuration with web thinning support efficient chip evacuation in through-hole and blind-hole applications. The straight cylindrical shank is compatible with standard drill chucks on bench drills, mag-base drills, and hand drills. It is a general-purpose workhorse across job sites and shop environments where consistent, accurate hole geometry is needed in metalworking applications.

Key Features

• Cobalt high-speed steel construction for increased heat and wear resistance in hard metals
• 135-degree split point reduces walk-off and lowers required feed force
• Straw oxide finish adds lubricity and extends cutting edge life
• Web-thinned tapered web improves chip evacuation and reduces thrust
• Right-hand cut, regular spiral flute — 2-flute design for standard metal drilling
• Meets NAS 907 and ANSI standards for dimensional accuracy and material grade

Compatibility

Designed for use in standard drill chucks accepting a 0.6719-inch straight cylindrical shank. Part of the PRECISION TWIST DRILL Series R10CO-R15CO-R18CO cobalt jobber drill line. Suitable for drilling steel, stainless steel, cast iron, and similar metals per primary workpiece material codes P, M, K, N, and S.

Installation Notes

Installation should be performed by a qualified machinist or trade professional following applicable shop safety procedures. Ensure the drill press or handheld drill is powered off and the chuck is fully tightened before operation. Cutting fluid or coolant is recommended when drilling hard alloys to manage heat, even though this bit does not have through-coolant capability. Always verify workpiece is securely clamped before applying feed pressure.