Precision Twist Drill 5998683 Letter J Jobber Drill Bit

Product Description

The PRECISION TWIST DRILL 5998683 is a Letter J jobber-length drill bit designed for general-purpose drilling in metal and hard materials. It measures 0.277 inches in diameter with a 118-degree standard point angle and a steam oxide coating that reduces friction and provides mild corrosion resistance during storage and use. The two-flute, right-hand spiral design produces consistent chip evacuation in a wide range of ferrous and non-ferrous workpieces. Overall length is 4.125 inches with a 2.875-inch flute length, giving a 10xD depth-to-diameter ratio. The straight-cylindrical shank seats directly in standard drill chucks. Licensed HVAC techs, machinists, pipefitters, and general trade mechanics will find this bit appropriate for standard production drilling tasks.

This drill bit is suited for drilling steel, stainless steel, cast iron, non-ferrous metals, superalloys, and titanium. The steam oxide finish makes it a reliable choice for shop environments where light rust inhibition on stored tooling is valued. The regular spiral and tapered web configuration with web thinning reduce thrust force at the point, which is especially useful when drilling tougher alloys. It fits standard drill press and hand-drill chucks and is appropriate for both bench and field applications where a letter-series drill size is required.

Key Features

• Letter J size, 0.277 inches diameter, straight-cylindrical shank for use in standard drill chucks
• 118-degree standard point angle with web-thinned, tapered web for reduced thrust on entry
• Steam oxide coating reduces friction and provides light corrosion resistance
• High speed steel construction handles steel, stainless steel, cast iron, non-ferrous metals, superalloys, and titanium
• Regular right-hand spiral with 2-flute design for efficient chip clearance
• Meets ANSI standards and NAS 907 specification

Compatibility

Designed as a general-purpose jobber drill bit compatible with any standard drill chuck accepting a 0.277-inch straight-cylindrical shank, across Series R10A-R15A-R18A.

Installation Notes

This bit is installed by trade mechanics, machinists, and maintenance professionals using a standard keyed or keyless drill chuck. Secure the shank fully in the chuck before drilling and verify chuck runout on precision work. Use appropriate cutting fluid or coolant when drilling stainless steel, superalloys, or titanium to extend tool life. Inspect the cutting edges for wear or chipping before each use and replace the bit if the point is damaged.