Osg 1400126808 Thread Forming Tap 1/4-20 Unc Cobalt Ticn

Product Description

The OSG 1400126808 is a thread forming tap in the HY-PRO NRT series, designed for right-hand, blind hole threading in a 1/4-20 UNC thread form. Unlike cutting taps, this modified bottoming style tap forms threads by displacing material rather than cutting chips, producing stronger threads with a better surface finish. Built from cobalt high-speed steel and coated with TiCN for improved wear resistance and heat tolerance, it handles demanding applications across a broad range of workpiece materials. The overall length is 2.5 inches, with a thread length of 0.594 inches and a tapping depth of 0.933 inches. Thread limit is H10. Intended for use by machinists and maintenance professionals in production and repair environments.

This tap is suited for blind hole threading in materials including alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel. The modified bottoming chamfer — 2 to 2.5 chamfered threads — allows threading close to the bottom of a blind hole. The HY-PRO NRT series is engineered for use in applications where chip removal is a concern or where rolled threads are preferred for improved tensile strength. It is appropriate for use in both manual and CNC tapping operations where a 1/4-20 UNC thread is required.

Key Features

• Thread forming (roll tap) design eliminates chips in blind hole applications
• Cobalt construction for increased heat and wear resistance over standard HSS
• TiCN coating extends tool life in abrasive and hard materials
• Modified bottoming chamfer (2 to 2.5P) allows threading close to hole bottom
• H10 thread limit for tight tolerance control
• No coolant-through design — suitable for standard tapping fluid or paste lubricant

Compatibility

Designed for blind hole threading of 1/4-20 UNC threads in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces. Material application codes P and N apply.

Installation Notes

Thread forming taps require a specific tap drill size optimized for roll tapping — verify the correct drill diameter for the material and thread engagement percentage before use. Always apply an appropriate tapping fluid or cutting compound; thread forming generates higher torque than cutting taps, so use a torque-limiting tap holder when possible. Power down or disengage the spindle before repositioning the workpiece. Follow applicable shop safety procedures and manufacturer tool-life guidelines for cobalt tooling in hardened materials.