Osg 1400128601 Thread Forming Tap 1/4-28 Unf Cobalt H6

Product Description

The OSG 1400128601 is a thread forming tap designed for creating internal threads without cutting, using material displacement to produce strong, chip-free threads. Built from cobalt high-speed steel with a steam oxide coating, this tap is rated for right-hand, blind hole threading in a 1/4-28 UNF configuration. The modified bottoming chamfer — 2 to 2.5 chamfered threads — allows threading close to the bottom of a blind hole while maintaining controlled entry. With an H6 thread limit, it holds tight tolerances suited for precision assemblies. Machinists, toolmakers, and maintenance mechanics install this tap in manual or CNC tapping applications across a wide range of metalworking operations.

This tap is built for threading blind holes in a broad spectrum of materials, including alloy steel, carbon steel, die steel, hardened steel, stainless steel, and aluminum. The HY-PRO NRT series is engineered for high-performance forming applications where chip evacuation is a concern or thread strength needs to exceed what cut taps can deliver. Typical use cases include production machining, toolroom work, and repair threading in tight-tolerance components. The steam oxide finish reduces friction during forming and helps the tap release from the workpiece cleanly.

Key Features

• Thread forming (chipless) design eliminates chip evacuation issues in blind holes
• Cobalt construction provides heat and wear resistance in tough alloys and hardened steels
• Steam oxide coating reduces friction and galling during the forming process
• Modified bottoming chamfer (2 to 2.5P) allows threading close to hole bottom
• H6 thread limit holds precision tolerances for tight-fit assemblies
• Right-hand thread direction, compatible with standard tapping equipment

Compatibility

Designed for blind hole threading in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces. Material application codes P and N confirm suitability across ferrous and non-ferrous stock within the HY-PRO NRT series 14001 family.

Installation Notes

Thread forming taps require a properly sized forming tap drill — standard twist drill charts do not apply; consult a forming tap drill size reference before drilling. Use a cutting or forming fluid appropriate for the workpiece material to reduce heat and extend tap life. Ensure the tap is driven in true alignment with the hole to prevent thread distortion or tap breakage. Follow shop or facility safety procedures when operating tapping equipment, including securing the workpiece and using appropriate RPM for the material and tap diameter.