Hertel 04138772 Cobalt Jobber Drill No 30 135 Deg

Product Description

The HERTEL 04138772 is a cobalt jobber-length drill bit designed for heavy-duty holemaking in ferrous metals, stainless steel, and other hard materials that standard HSS bits struggle to penetrate. Built to a No. 30 wire gauge size, it measures 0.1285 inches in diameter with an overall length of 2.75 inches and a flute length of 1.625 inches. The 135-degree split point reduces walking on entry and requires less thrust to start a hole, which matters in production or repetitive drilling environments. The oxide and TiN coating improves surface hardness and extends tool life under continuous use. This is a right-hand, regular-spiral, straight-cylindrical shank bit sold individually.

This drill bit is suited for metalworking tradespeople, maintenance technicians, and machinists who need a reliable small-diameter bit for precision holemaking in tough base materials. Typical applications include drilling pilot holes, clearance holes, and through-holes in steel plate, alloy steels, castings, and similar hard substrates. The cobalt construction makes it a practical choice where heat buildup is a concern, such as in manual drill press work, hand-held drilling in tight spaces, or light CNC operations. The web-thinned, tapered web geometry reduces cutting resistance at depth.

Key Features

• Cobalt steel construction for high heat resistance and durability in hard metals
• 135-degree split point reduces drill walk and lowers required entry thrust
• Oxide and TiN coating improves wear resistance and extends service life
• Right-hand, regular spiral flute for efficient chip evacuation
• Web-thinned tapered web reduces cutting resistance at depth
• Straight-cylindrical shank fits standard drill chucks without adapters

Compatibility

Designed as an OEM-style jobber drill for use in standard drill chucks accepting a 0.1285-inch straight-cylindrical shank, compatible with drill presses, hand drills, and light CNC spindles within the No. 30 wire size range of 0.1000 to 0.1500 inches.

Installation Notes

Installed by machinists, maintenance mechanics, or metalworking tradespeople using a drill press or hand-held power drill. Ensure the chuck is fully tightened and the workpiece is secured before drilling. Use appropriate cutting fluid or coolant when drilling stainless steel or alloy steels to manage heat and extend bit life. Inspect the cutting edge before each use and replace the bit if chipping or dulling is visible.