Emuge CU513510.5621 Cobalt Sti Tap 1/2-13 Unc 4 Flute

Product Description

The EMUGE CU513510.5621 is a cobalt spiral flute STI (Screw Thread Insert) tap designed for cutting 1/2-13 UNC internal threads in demanding materials. Built to Enorm Z series standards, this tap features a 4-flute, 45-degree right-hand helix geometry and a bottoming chamfer for threading close to the bottom of blind holes. The bright finish cobalt construction delivers heat and wear resistance well beyond standard high-speed steel taps. Overall length is 4.331 inches, with a 0.48-inch shank diameter and a 1-1/16-inch thread length. It produces Class 3B fits, meeting tight-tolerance thread requirements common in precision and structural applications.

This tap is suited for use in a wide range of materials including stainless steel, titanium alloys, nickel and nickel alloys, acid-resistant steel, aluminum alloys, free cutting steel, heat-treated steel, high alloy steel castings, tool steel, steel castings, and structural steel. It is intended for machinists and tool-and-die professionals working on production or repair applications where STI thread inserts are required. The 45-degree spiral flute geometry aids chip evacuation in both through and blind hole configurations, making it practical across CNC machining centers and manual tapping setups.

Key Features

• Cobalt material construction for superior heat resistance and extended tool life in hard and abrasive materials
• 45-degree right-hand helix promotes efficient chip evacuation during tapping
• Bottoming chamfer allows threading to the full depth of blind holes
• 4-flute design provides rigidity and smooth thread form in a 1/2-13 UNC profile
• Class 3B fit ensures tight-tolerance threads compatible with precision fastener applications
• Bright finish reduces friction and facilitates chip flow without coating buildup

Compatibility

Designed for cutting 1/2-13 UNC Class 3B STI threads in acid-resistant steel, aluminum alloys, free cutting steel, heat-treated steel, heat-treated materials, high alloy steel castings, nickel, nickel alloys, stainless steel, steel castings, structural steel, titanium alloys, and tool steel.

Installation Notes

This tap is intended for use by qualified machinists familiar with STI tapping procedures and appropriate cutting fluid selection for the workpiece material. Always secure the workpiece fully and ensure the tapping fixture or CNC spindle is properly aligned before engaging the tap. Power down or disengage the machine spindle before changing tooling. Follow applicable shop safety standards and machine tool operating guidelines when working with cobalt cutting tools.