Osg 1400127205 Thread Forming Tap 1/4-20 Unc Plug Cobalt

Product Description

The OSG 1400127205 is a thread forming tap in the HY-PRO NRT series, designed for cold-forming internal threads without cutting. It produces a 1/4-20 UNC right-hand thread using a plug chamfer with 4 to 4.5 chamfered threads for reliable thread entry. The tap is manufactured from cobalt high-speed steel with a TiN coating, delivering extended tool life in demanding applications. Overall length is 2.5 inches, thread length is 0.594 inches, and shank diameter is 0.255 inches. It carries an H5 thread limit for controlled fit. This tool is installed by machinists and maintenance professionals working in production and repair environments.

This tap is suited for through-hole threading operations across a wide range of workpiece materials. Rated material applications include alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel, making it a versatile choice for job shops, maintenance facilities, and production floors. The plug chamfer style is the standard choice for through-hole work where the tap can advance fully through the material. Tapping depth reaches 0.933 inches, supporting typical fastener engagement requirements in 1/4-20 applications.

Key Features

• Thread forming (chipless) design eliminates chip clearance concerns in blind and through holes
• Cobalt HSS construction resists heat and wear in tough alloys and hardened steels
• TiN coating reduces friction and extends tool life across repeated use cycles
• H5 thread limit ensures consistent fit for standard UNC tolerance applications
• Plug chamfer with 4 to 4.5 chamfered threads provides controlled thread entry in through-hole work
• Right-hand thread direction compatible with standard tapping equipment and CNC setups

Compatibility

Designed for through-hole threading applications in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces. Material application codes P and N confirm suitability for steels and non-ferrous metals. Compatible with standard 1/4-inch drive tap handles, tapping arms, and CNC tapping cycles that accept straight-shank taps with a 0.255-inch shank diameter.

Installation Notes

Thread forming taps require a properly sized forming tap drill hole, which differs from a cutting tap drill size - consult the appropriate forming tap drill chart for 1/4-20 UNC before drilling. Apply tapping fluid or cutting oil rated for the workpiece material to reduce friction and protect the TiN coating. Secure the workpiece and ensure the tap is started square to the hole to avoid thread distortion. This tap does not produce chips, but the work area and tooling should still be cleaned between operations to prevent contamination of the formed threads.