Hertel 87703914 Cobalt Drill Bit No. 30 135 Split Point

Product Description

The HERTEL 87703914 is a cobalt threaded shank drill bit sized at No. 30 (0.1285 inches decimal) with a 135-degree split point and a 1/4-28 threaded square shank. The split point geometry and web-thinned, tapered web configuration reduce thrust and allow the bit to self-center without a pilot hole. Oxide coating provides moderate corrosion resistance and helps manage heat during cutting. The short-pattern body keeps overall length at 1.25 inches with a 9/16-inch flute length, making it suited for tight-clearance drilling applications. Right-hand spiral flutes evacuate chips efficiently during standard rotary drilling operations.

This bit is rated for general-purpose use in high-tensile strength metals, including alloy steels, stainless steels, and other hard ferrous materials where standard HSS tooling underperforms or dulls prematurely. The 1/4-28 threaded shank is designed for use with quick-change threaded-shank drill holders and tooling systems common in aerospace, maintenance, and precision fabrication environments. Its short overall length suits applications where clearance is limited or rigidity is a priority. The NAS 965 Type D specification indicates conformance to a recognized aerospace-grade dimensional standard.

Key Features

• No. 30 wire gauge size — 0.1285 inches decimal equivalent
• 135-degree split point with web thinning for self-centering and reduced feed force
• Cobalt construction with oxide coating for heat and wear resistance in hard metals
• 1/4-28 threaded square shank for use with compatible quick-change tooling systems
• Short-pattern body — 1.25 inches overall length, 9/16-inch flute length — for tight-clearance access
• Conforms to NAS 965 Type D specification

Compatibility

Designed for use with 1/4-28 threaded-shank drill holders and quick-change tooling systems that accept this shank thread size. Suitable for drilling high-tensile strength metals including alloy and stainless steels.

Installation Notes

Installation and use of this bit should be performed by qualified machinists, maintenance technicians, or fabricators familiar with rotary drilling equipment and speed-and-feed selection for cobalt tooling. Ensure the drill holder is fully engaged and the threaded shank is seated securely before operation. Select appropriate spindle speed and feed rate for the workpiece material to avoid overheating the cutting edge. Coolant-through operation is not supported by this bit; use external cutting fluid when drilling hard or heat-sensitive alloys.