Osg 1400127105 Thread Forming Tap 1/4-20 Unc Plug Cobalt Tin

Product Description

The OSG 1400127105 is a thread forming tap in the HY-PRO NRT series, designed for cold-forming internal threads without cutting chips. Operating on a 1/4-20 UNC thread profile with a plug chamfer, this tap displaces material rather than removing it, producing stronger threads with better surface finish in ductile materials. Built from cobalt high-speed steel and finished with a TiN coating, it carries an H4 thread limit and a right-hand thread direction. Overall length is 2.5 inches with a thread length of 0.594 inches and a tapping depth of 0.933 inches. It is installed by machinists, tool-and-die technicians, and maintenance mechanics working in production or repair environments.

This tap is suited for through-hole threading applications in a wide range of ferrous and non-ferrous materials including alloy steel, carbon steel, die steel, hardened steel, stainless steel, and aluminum. The plug chamfer with 4 to 4.5 chamfered threads makes it appropriate for through-hole entry where the tap can engage progressively. It fits production tapping on CNC machining centers and manual tapping operations where chip-free thread forming is preferred for cleanliness and thread integrity.

Key Features

• Thread forming (chipless) design produces stronger threads by cold-working material fibers
• Cobalt HSS construction provides elevated heat and wear resistance versus standard M2 HSS
• TiN coating reduces friction and extends tool life across high-volume tapping cycles
• H4 thread limit provides tolerance control for close-fit UNC thread requirements
• Plug chamfer with 4 to 4.5 chamfered threads suits through-hole entry and standard tapping conditions
• Right-hand thread direction, no coolant-through requirement — compatible with standard tapping arms and CNC rigid tapping

Compatibility

Designed for through-hole thread forming in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces. Material application codes P and N apply. Verify minimum hole size requirements for thread forming before use, as pre-drill diameter differs from cutting tap requirements.

Installation Notes

Thread forming taps require a larger pilot hole than cutting taps for the same thread size — consult the OSG HY-PRO NRT drill size chart before drilling. Use tapping fluid or cutting oil appropriate for the workpiece material, particularly when working stainless or hardened steel. Secure the workpiece fully and apply consistent axial pressure to prevent tap breakage, especially at entry. On CNC equipment, use rigid tapping mode with synchronized spindle and feed to match the 20 threads-per-inch pitch.