Precision Twist Drill 5999549 Taper Length Drill Bit

Product Description

The PRECISION TWIST DRILL 5999549 is a taper length drill bit designed for general-purpose drilling across a wide range of materials. It measures 0.2380 inches in diameter, corresponding to Letter B sizing, with an overall length of 6.125 inches and a flute length of 3.75 inches. Machined from high speed steel with a bright, uncoated finish, this bit features a standard 118-degree point angle and a right-hand spiral flute. The straight shank measures 0.2380 inches and fits standard drill chucks without modification. It is a Series R55 bit with web thinning applied, which reduces the chisel edge and lowers the thrust force needed at the start of a cut. Machinists, maintenance technicians, and fabricators install this type of bit in drill presses, lathes, and hand-held power drills.

This bit is rated for general-purpose use across a broad spectrum of metals and engineered materials. Suitable material applications include alloy steel, carbon steel, hardened steel, stainless steel, cast iron, malleable iron, aluminum, aluminum alloy, brass, bronze, high strength bronze, copper, nickel, nickel alloy, magnesium, magnesium alloy, cermet, graphite, and reinforced plastic materials. The 6xD flute-length-to-diameter ratio provides added clearance for deeper hole drilling compared to a standard jobber-length bit, making it well suited for applications where a longer reach is required without stepping up to a full extended-length bit.

Key Features

• Letter B size at 0.2380 inches diameter with matching straight shank for direct chuck mounting
• High speed steel construction provides heat resistance for drilling ferrous and non-ferrous metals
• 118-degree standard point angle for general-purpose entry on flat and curved workpieces
• Web-thinned tapered web reduces drilling thrust and minimizes walking at bit start
• 3.75-inch flute length at a 6xD ratio allows deeper cuts than standard jobber-length bits
• Bright, uncoated finish suitable for use with or without cutting fluid
• Meets ANSI standards for drill bit geometry and tolerance

Compatibility

Designed as a general-purpose replacement or supplemental taper-length drill bit for use in standard 3-jaw chucks accepting a 0.2380-inch straight shank. Compatible with drill presses, milling machines, and hand-held power drills where the Series R55 taper length format is specified.

Installation Notes

A licensed machinist or qualified maintenance technician should verify chuck capacity and spindle speed before mounting this bit. Secure the straight shank firmly in the chuck jaws with no runout before beginning a cut. Apply appropriate cutting fluid when drilling stainless steel, hardened steel, or other hard ferrous alloys to extend tool life and improve hole quality. Inspect the cutting edges for wear or chipping before each use and replace the bit if the point geometry is compromised.