Precision Twist Drill 5999428 No 44 Hss Jobber Drill Bit

Product Description

The PRECISION TWIST DRILL 5999428 is a No. 44 wire-size jobber-length drill bit machined from high speed steel (HSS) and finished with a steam oxide coating to reduce friction and extend tool life in production drilling applications. The bit features a 118-degree standard point angle, a right-hand cutting direction, and a regular spiral flute with a tapered, web-thinned web configuration that improves chip evacuation and reduces thrust when entering the workpiece. Overall length is 2.125 inches with a 1.125-inch flute length and a straight cylindrical shank. This bit conforms to ANSI standards and meets NAS 907 specification, making it a reliable choice for shops requiring documented tool traceability.

This drill bit is suited for general-purpose drilling in steel and cast iron, as well as non-ferrous and other common workpiece materials coded P, M, K, N, and S in the ISO material classification system. The No. 44 wire gauge diameter of 0.0860 inches makes it appropriate for small-diameter through-hole and blind-hole drilling in sheet metal, structural steel, and light cast iron components. It is commonly used by machinists, tool-and-die technicians, and maintenance mechanics in job-shop and production environments. The flute-to-diameter ratio of 13xD supports drilling to a maximum depth of 1.125 inches without extended-length tooling.

Key Features

• No. 44 wire size, 0.0860-inch decimal diameter for precise small-hole work
• 118-degree standard point angle with web-thinned, tapered web for reduced entry thrust
• High speed steel construction for general-purpose cutting across steel and cast iron
• Steam oxide coating reduces friction and provides light corrosion resistance during storage and use
• Right-hand, regular spiral flute promotes efficient chip evacuation in common workpiece materials
• Meets ANSI standards and NAS 907 specification for traceable tooling applications

Compatibility

Part of the PRECISION TWIST DRILL Series R10A-R15A-R18A jobber drill line. Designed as a general-purpose replacement or production drill bit for use in any standard drill press, CNC machining center, or hand-held drill motor equipped with a chuck capable of accepting a 0.0860-inch straight shank.

Installation Notes

Installation is performed by machinists or maintenance mechanics using a standard keyed or keyless drill chuck. Ensure the shank is fully seated and the chuck is tightened securely before operation to prevent runout or bit slippage. For drilling in steel or cast iron, use an appropriate cutting fluid or coolant to manage heat buildup, as this bit is not rated for coolant-through delivery. Inspect the point and cutting edges for wear or chipping before each use and replace the bit if edge integrity is compromised.