Osg 1400127400 Thread Forming Tap 1/4-20 Unc Plug Cobalt

Product Description

The OSG 1400127400 is a thread forming tap designed for right-hand, through-hole threading in a 1/4-20 UNC thread form. Part of the HY-PRO NRT series, it is manufactured from cobalt high-speed steel with a bright finish and carries an H7 thread limit for consistent fit and dimensional accuracy. The plug chamfer, with 4 to 4.5 chamfered threads, provides a controlled lead-in that suits through-hole applications across a range of workpiece materials. Overall length is 2.5 inches with a thread length of 0.594 inches and a shank diameter of 0.255 inches. Machinists and toolroom technicians working in production or maintenance environments will find this tap suited for consistent, repeatable results.

This tap is intended for through-hole threading operations in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel. The thread forming method displaces material rather than cutting it, which eliminates chips and reduces the risk of tap breakage in blind or through-hole setups. It is well suited for CNC machining centers, drill presses, and tapping machines in industrial, maintenance, and job shop environments where 1/4-20 UNC threads are a common requirement.

Key Features

• Thread forming design displaces material rather than cutting, producing no chips and stronger formed threads
• Cobalt high-speed steel construction provides heat and wear resistance in harder workpiece materials
• H7 thread limit ensures dimensional consistency and proper fit with mating fasteners
• Plug chamfer with 4 to 4.5 chamfered threads for reliable lead-in on through-hole applications
• Bright finish with no coolant-through requirement simplifies tooling setup
• Right-hand thread direction compatible with standard tapping equipment

Compatibility

Designed for through-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 the correct tap drill size for the material being threaded; using a standard cutting-tap drill diameter will result in incorrect thread form and potential tap damage. Ensure the workpiece is securely fixtured and the tapping spindle is properly aligned before operation. Appropriate tapping fluid or cutting lubricant should be applied for the specific workpiece material to extend tap life. Follow all machine guarding and lockout-tagout procedures before changing or inspecting tooling.