Hertel 4140307 Cobalt Jobber Drill No. 38 0.1015 in

Product Description

The HERTEL 4140307 is a cobalt jobber-length drill bit in wire gauge size No. 38, with a decimal diameter of 0.1015 inches. It features a 135-degree split point for fast, self-centering starts with minimal walking on hardened, stainless, and high-strength alloy materials. The TiAlN coating adds surface hardness and heat resistance, extending tool life in demanding cutting applications. With a 2.5-inch overall length and straight-cylindrical shank, this drill fits standard three-jaw chucks on benchtop drill presses, hand drills, and CNC machining centers. It is suited for metalworking tradespeople, maintenance mechanics, and fabricators working with tough or abrasive workpiece materials.

This drill bit targets applications in metal fabrication, industrial maintenance, and precision holemaking where wire-gauge sizing is required. The heavy-duty cobalt construction handles interrupted cuts and high-heat conditions better than standard HSS bits. Typical uses include drilling stainless steel, hard alloys, titanium, and cast iron in both shop and field environments. The jobber series length provides a practical balance of reach and rigidity for through-hole drilling in plate, tube, and structural stock up to the bit's capacity.

Key Features

• Cobalt construction rated heavy duty for high-heat and abrasive material drilling
• TiAlN coating increases surface hardness and reduces heat buildup at the cutting edge
• 135-degree split point with web thinning allows self-centering starts without a center punch on most metals
• Right-hand spiral flute with regular helix provides efficient chip evacuation
• Straight-cylindrical shank at 0.1015 inches diameter fits standard drill chucks without adapters
• No coolant-through requirement simplifies use in standard hand-held and benchtop setups

Compatibility

Designed for use in standard three-jaw drill chucks accepting a 0.1015-inch straight shank; compatible with drill presses, hand drills, and CNC machining centers configured for jobber-length drill bits in the 0.1000 to 0.1500 inch diameter range.

Installation Notes

Secure the straight shank firmly in a properly sized drill chuck before operation and verify chuck key is removed before starting the spindle. Use appropriate cutting fluid or lubricant when drilling stainless steel or hard alloys to prolong edge life, even though the TiAlN coating provides dry-cutting capability. Wear ANSI-rated eye protection and secure the workpiece in a vise or fixture to prevent spinning. Inspect the cutting edges for wear or chipping before each use, as a damaged split-point geometry will degrade hole quality and increase thrust force.