Precision Twist Drill 5999434 Jobber Drill Bit Letter W

Product Description

The PRECISION TWIST DRILL 5999434 is a jobber-length drill bit sized to letter W (0.3860 inches decimal equivalent), designed for general-purpose drilling in a wide range of materials. Built from high speed steel with a steam oxide coating, it offers corrosion resistance and reduced friction during cutting. The 118-degree standard point angle suits most common drilling applications across ferrous and non-ferrous stock. With an overall length of 5.125 inches and a 3.75-inch flute length, this bit fits standard drill chucks and handles the majority of through-hole and blind-hole work encountered in fabrication and maintenance settings. Licensed tradespeople and machinists install this bit in hand drills, drill presses, and milling setups.

This bit is suited for drilling steel, stainless steel, cast iron, non-ferrous metals, superalloys, and titanium. The regular spiral flute and two-flute geometry provide efficient chip evacuation in these materials. It falls within the R10-R15-R18 series from PRECISION TWIST DRILL, covering the 0.3500 to 0.4000 inch diameter range. Typical applications include structural fabrication shops, maintenance and repair operations, and production drilling environments where a straight-cylindrical shank and consistent geometry are required.

Key Features

• Letter W size with 0.3860 inch decimal equivalent for precise hole sizing
• 118-degree standard point angle with web-thinned, tapered web for easier starting and reduced thrust
• Steam oxide coating provides corrosion resistance and reduces built-up edge during cutting
• Two-flute regular spiral design promotes efficient chip removal from the cut zone
• Straight-cylindrical shank fits standard drill chucks without adapters
• ANSI-standard geometry ensures dimensional consistency across replacement bits

Compatibility

Designed as a general-purpose jobber-length drill bit compatible with any standard drill chuck accepting a 0.3860 inch straight-cylindrical shank, including bench drill presses, hand drills, and CNC drilling setups configured for straight-shank tooling.

Installation Notes

Installation is performed by machinists, maintenance technicians, or fabricators using a keyed or keyless drill chuck rated for the shank diameter. Secure the shank fully in the chuck before beginning any drilling operation and verify chuck tightness. Always power down and de-energize the drill press or machine before changing bits. Do not exceed the maximum drilling depth of 3.75 inches without retracting to clear chips.