Precision Twist Drill 5998680 Drill Bit Letter I Hss

Product Description

The PRECISION TWIST DRILL 5998680 is a jobber-length drill bit in Letter I size, equivalent to 0.272 inches in diameter. Made from high-speed steel with a steam oxide coating, this two-flute bit features a standard 118-degree point angle and a web-thinned, tapered web configuration for improved chip clearance and reduced thrust during entry. It cuts in a right-hand direction with a regular spiral flute pattern and a straight-cylindrical shank. Designed for general-purpose drilling in production and maintenance environments, this bit is installed and used by machinists, maintenance technicians, pipefitters, and other trade professionals requiring precise hole sizing.

This drill bit is suited for drilling into a range of materials including steel, stainless steel, cast iron, non-ferrous metals, superalloys, titanium, and other hard materials. It is appropriate for use in hand-held drill motors, drill presses, and CNC drilling operations. The 4.125-inch overall length and 2.875-inch flute length make it well-matched to standard jobber-length applications in both shop and field settings. The steam oxide finish provides light corrosion resistance and helps reduce friction during cutting.

Key Features

• Letter I size — 0.272 inches diameter — for precise hole sizing in standard letter-series applications
• 118-degree standard point angle with web-thinned, tapered web for reduced entry thrust
• High-speed steel construction suitable for steel, stainless steel, cast iron, non-ferrous metals, superalloys, and titanium
• Steam oxide coating provides light corrosion resistance and friction reduction
• Right-hand cut, regular spiral flute for efficient chip evacuation
• Straight-cylindrical shank compatible with standard drill chucks
• Meets ANSI and NAS 907 standards; Series R10A-R15A-R18A

Compatibility

Designed as a general-purpose jobber-length drill bit for use in standard drill chucks accepting a 0.272-inch straight-cylindrical shank across drill presses, hand drills, and CNC drilling equipment.

Installation Notes

This bit is installed by machinists, pipefitters, and maintenance technicians using standard keyed or keyless drill chucks. Secure the shank fully in the chuck before operation and confirm the workpiece is clamped or fixtured to prevent movement. Use appropriate cutting fluid or lubrication when drilling steel, stainless steel, or superalloys to extend tool life and maintain hole quality. Inspect the cutting edges for wear or chipping before each use and replace the bit if the point is damaged.