Precision Twist Drill 5997674 Cobalt Jobber Drill Bit

Product Description

The PRECISION TWIST DRILL 5997674 is a cobalt jobber-length drill bit in No. 1 wire gauge size, equivalent to 0.2280 inches in diameter. It features a 135-degree split point with web thinning for fast, self-centering starts on steel and other hard materials, reducing the need for a center punch. The straw oxide finish provides light lubricity and heat resistance during high-speed drilling. With an overall length of 3.875 inches and a 2.625-inch flute, this bit is built for heavy-duty general-purpose drilling in ferrous and non-ferrous metals. It conforms to ANSI standards and carries a NAS 907 specification designation. Licensed HVAC, mechanical, and plumbing contractors as well as metalworking professionals will find this a reliable production-grade tool.

This bit is suited for drilling steel, stainless, cast iron, and other demanding workpiece materials encountered in fabrication shops, field service, and maintenance applications. The regular spiral flute with a 12xD flute-to-diameter ratio handles chip evacuation effectively in through-hole and blind-hole operations. The straight cylindrical shank with zero flats mounts directly in standard three-jaw keyed or keyless drill chucks. It belongs to the Series R10CO-R15CO-R18CO family of cobalt drill bits from Precision Twist Drill, which are designed for extended tool life in abrasive and hard-material applications.

Key Features

• Cobalt high-speed steel construction for heat resistance and extended tool life in hard materials
• 135-degree split point with web thinning for self-centering starts without a pilot hole
• Straw oxide coating provides light lubricity and corrosion resistance during cutting
• Regular spiral flute with tapered web configuration promotes efficient chip evacuation
• Straight cylindrical shank fits standard drill chucks without adapters
• Conforms to ANSI standards and NAS 907 specification for dimensional accuracy

Compatibility

Part of the Precision Twist Drill Series R10CO-R15CO-R18CO cobalt jobber drill line. Designed for use in standard three-jaw drill chucks on benchtop drill presses, hand drills, and CNC drilling equipment where a 0.2280-inch straight shank is accepted. Primary workpiece material codes P, M, K, N, and S indicate suitability for steel, stainless steel, cast iron, non-ferrous metals, and high-temperature alloys per ISO material classification.

Installation Notes

Secure the shank fully in the drill chuck before operation and verify chuck tightness with a chuck key where applicable. Use cutting fluid or coolant on steel and stainless workpieces to extend bit life and control heat buildup; this bit does not support coolant-through delivery. Replace the bit if cutting edges show visible chipping or if the drill begins to wander during entry. Observe applicable shop safety practices including eye protection and workpiece clamping as required by OSHA and facility standards.