Precision Twist Drill 5998031 7/16 in Hss Jobber Drill Bit

Product Description

The PRECISION TWIST DRILL 5998031 is a 7/16 inch diameter jobber length drill bit engineered for general-purpose and heavy-duty drilling applications. Built from high speed steel (HSS) with a steam oxide coating, it resists heat buildup and corrosion during extended drilling cycles. The 135-degree split-point tip reduces walking on entry and cuts through material with less feed pressure than a standard 118-degree point. The web-thinned, tapered web design improves chip evacuation. Licensed machinists, pipefitters, HVAC fabricators, plumbers, and electricians routinely use jobber-length bits like this one for hole placement in panel work, ductwork layout, and structural drilling tasks.

This bit is suited for drilling steel, stainless steel, cast iron, non-ferrous metals, superalloys, titanium, and other hard materials. It follows ANSI standards and carries a NAS 907 specification designation, making it appropriate for both shop fabrication and field service work. The R10B series covers the 0.4000 to 0.5000 inch diameter range and is a recognized general-purpose jobber series. Maximum drilling depth is 4-1/16 inches, making this bit appropriate for through-hole work in standard structural and sheet stock thicknesses.

Key Features

• 135-degree standard point angle with web thinning reduces entry walking and lowers required feed force
• Steam oxide coating improves lubricity and heat resistance during continuous drilling
• High speed steel construction rated for steel, stainless steel, cast iron, non-ferrous metals, superalloys, and titanium
• Regular spiral flute with 2 flutes and a 9xD flute-to-diameter ratio for efficient chip clearance
• Straight-cylindrical shank at 7/16 inch diameter fits standard 3-jaw drill chucks without adapters
• NAS 907 specification and ANSI standards compliance for traceability in specification-driven work

Compatibility

Designed for use in standard 3-jaw drill chucks accepting a 7/16 inch straight-cylindrical shank. Part of the R10B-R15B-R18B series covering the 0.4000 to 0.5000 inch diameter range.

Installation Notes

Install in a drill press, hand drill, or magnetic base drill with a chuck rated for the 7/16 inch shank diameter. Ensure the chuck is fully tightened and the workpiece is clamped before drilling. Use appropriate cutting fluid or lubricant when drilling stainless steel, superalloys, or titanium to manage heat and extend tool life. Power down all equipment and secure the workpiece before changing or inspecting the bit.