Osg 1400137600 Thread Forming Tap 3/8-24 Unf Cobalt H7

Product Description

The OSG 1400137600 is a thread forming tap in the HY-PRO NRT series, designed for cold-forming internal threads without cutting. Sized at 3/8-24 UNF with a modified bottoming chamfer of 2 to 2.5 threads, it drives material to shape rather than removing chips, making it well-suited for blind hole applications where chip evacuation is a concern. Built from cobalt high-speed steel with a bright finish and an H7 thread limit, this tap handles demanding materials including alloy steel, stainless steel, hardened steel, and aluminum. Licensed machinists and toolroom technicians are the primary users.

This tap is applied in blind hole threading operations across a range of ferrous and non-ferrous workpiece materials. The modified bottoming chamfer allows threading close to the bottom of a blind hole while still providing enough lead for reliable thread form initiation. It is rated for use in alloy steel, carbon steel, die steel, hardened steel, stainless steel, and aluminum, covering material application codes P and N. Typical applications include precision machined components in aerospace, automotive, and industrial manufacturing environments where thread quality and hole integrity are critical.

Key Features

• Cold-forming design eliminates chips, reducing risk of chip packing in blind holes
• Cobalt construction provides heat and wear resistance in tough alloy and stainless steel materials
• Modified bottoming chamfer (2 to 2.5 threads) enables threading close to blind hole bottom
• H7 thread limit for Class 2B fit — suitable for standard tolerance threaded assemblies
• Right-hand thread direction, 3/8-24 UNF
• Bright finish with no coolant-through requirement, compatible with flood or brush-applied cutting fluid

Compatibility

Rated for use in alloy steel, carbon steel, die steel, hardened steel, stainless steel, and aluminum workpieces. Designed for blind hole threading applications requiring a 3/8-24 UNF internal thread to Class 2B fit with H7 thread limit.

Installation Notes

This tap is installed by machinists or toolroom technicians using a tapping machine, CNC machining center, or hand tap wrench. Power down or lock out the spindle before loading or changing taps. Verify proper tap drill size for the 3/8-24 UNF thread before drilling the pilot hole, as undersize or oversize holes will degrade thread form quality. Apply appropriate cutting fluid for the workpiece material to reduce tool wear and extend tap life.