Precision Twist Drill 5997743 No. 52 Cobalt Jobber Drill

Product Description

The PRECISION TWIST DRILL 5997743 is a wire-gauge jobber-length drill bit sized at No. 52 (0.0635 inches decimal equivalent) ground from cobalt high-speed steel with a straw oxide finish. The 135-degree split point geometry reduces walking on entry and lowers thrust force compared to a conventional 118-degree point, making it well suited for harder ferrous workpieces. The web-thinned, tapered web design further reduces cutting resistance. At 1.875 inches overall length with a 0.875-inch flute, this bit is sized for short-reach drilling applications where rigidity matters. Licensed HVAC, plumbing, and electrical contractors routinely keep cobalt wire-gauge bits on hand for drilling through steel enclosures, brackets, and structural members.

This bit is applied in general-purpose drilling of steel, stainless steel, cast iron, aluminum, and other materials covered under workpiece material codes P, M, K, N, and S. Typical install scenarios include drilling pilot or clearance holes in electrical panels, conduit support brackets, duct flanges, equipment frames, and mechanical room steel. The straight cylindrical shank seats directly in standard drill chucks without adapters. This bit is manufactured to ANSI and NAS 907 standards, making it suitable for both shop and field use across HVAC, electrical, and mechanical trades.

Key Features

• No. 52 wire size — 0.0635-inch decimal diameter for precision clearance and pilot hole work
• Cobalt high-speed steel construction for improved heat and wear resistance in steel drilling
• 135-degree split point reduces drill walk and lowers entry thrust force
• Web-thinned tapered web decreases cutting resistance and extends tool life
• Straw oxide finish provides mild lubricity and corrosion resistance during use
• Regular spiral, 2-flute design provides efficient chip evacuation in straight-through drilling
• Meets ANSI and NAS 907 standards for dimensional and performance consistency

Compatibility

Part of the PRECISION TWIST DRILL Series R10CO-R15CO-R18CO cobalt jobber drill line. Designed for general-purpose drilling in steel and multi-material applications across trade and industrial use. Fits any standard drill chuck accepting a 0.0635-inch straight cylindrical shank.

Installation Notes

This bit is installed and used by electricians, HVAC technicians, plumbers, and mechanical contractors performing field or shop drilling. Always ensure the workpiece is secured before drilling and use appropriate cutting fluid or lubricant when drilling hardened or stainless steel to extend bit life. Disconnect power or de-energize equipment before drilling into or near live electrical enclosures per NEC requirements. Do not exceed the recommended maximum drilling depth of 0.875 inches without retracting to clear chips.