Hertel 74132259 Screw Machine Drill Bit Size 28 Cobalt

Product Description

The HERTEL 74132259 is a screw machine length drill bit designed for high-speed, high-volume drilling in metal and hard materials. Built from cobalt steel and coated with TiAlN (Titanium Aluminum Nitride), it delivers extended tool life in demanding applications including stainless steel, cast iron, and hardened alloys. The 135-degree split point self-centers on entry, reducing the need for a center punch and minimizing walking on smooth or curved surfaces. At 1-15/16 inches overall length with a 15/16-inch flute, this stub-length geometry provides rigidity and reduces deflection in short-reach setups. The straight-cylindrical shank fits standard drill chucks without adapters.

This bit is suited for production machining environments, maintenance shops, and fabrication operations where a Number 28 wire gauge diameter (0.1405 inches) is required. It excels in CNC drilling centers, drill presses, and handheld drills where bit rigidity and heat resistance are priorities. The screw machine length format is a common choice for close-tolerance work in metalworking and mechanical assembly applications. A licensed machinist or journeyman maintenance tech would typically specify this bit for repetitive hole operations in ferrous and non-ferrous metals.

Key Features

• Cobalt steel construction resists heat buildup during extended drilling cycles in hard metals
• TiAlN coating increases surface hardness and reduces friction at the cutting edge
• 135-degree split point provides self-centering entry and reduced thrust force
• Web-thinned, parallel web configuration improves chip evacuation and reduces torque demand
• Stub screw machine length (1-15/16 inches OAL) maximizes rigidity and minimizes deflection
• Right-hand spiral flute with straight-cylindrical shank for universal chuck compatibility

Compatibility

Designed as an OEM-style replacement or standard tooling choice for any drill press, CNC machining center, or handheld drill accepting a straight-cylindrical shank bit in the Number 28 wire gauge size (0.1405 inches decimal equivalent).

Installation Notes

Installation of drill bits should be performed by a qualified machinist or maintenance technician. Ensure the drilling machine is fully powered down and locked out before changing tooling. Inspect the chuck or collet for wear before seating the shank, and tighten securely to prevent slippage under load. Do not exceed the drill press or machine spindle speed recommendations for the material being drilled.