Osg 1400137605 Thread Forming Tap 3/8-24 Unf Cobalt Tin

Product Description

The OSG 1400137605 is a thread forming tap in the HY-PRO NRT series, designed for cold-forming internal threads without cutting or producing chips. Built from cobalt high-speed steel with a titanium nitride (TiN) coating, it delivers strong wear resistance and extended tool life in demanding threading applications. The modified bottoming chamfer with 2 to 2.5 chamfered threads allows threading close to the bottom of a blind hole. Sized for 3/8-24 UNF threads with a right-hand direction and H7 thread limit, it suits precision threading where a Class 2B fit is required. This tap is sold individually and intended for use by machinists and toolroom professionals.

This tap is rated for blind hole threading across a wide range of ferrous and non-ferrous materials, including alloy steel, carbon steel, die steel, hardened steel, stainless steel, and aluminum. The HY-PRO NRT series is suited for production and job shop environments where chipless thread forming is preferred over conventional cutting taps. Its cobalt substrate handles the higher temperatures and pressures generated during form tapping in tough alloys. Material application codes P and N indicate suitability for steel and non-ferrous material groups.

Key Features

• Thread forming (chipless) design eliminates chip evacuation concerns in blind holes
• Cobalt high-speed steel construction for heat and wear resistance in tough materials
• TiN coating reduces friction and extends tool life across production runs
• Modified bottoming chamfer (2 to 2.5 threads) allows threading close to hole bottom
• H7 thread limit and Class 2B fit for precision tolerance control
• Right-hand, 3/8-24 UNF configuration covers common fine-thread fastener applications

Compatibility

Designed for blind hole threading in alloy steel, carbon steel, die steel, hardened steel, stainless steel, and aluminum. Compatible with standard 3/8-inch tap holders and chucks accepting a 0.381-inch shank diameter.

Installation Notes

Thread forming taps require a properly sized forming tap drill — consult OSG or standard tap drill charts for the correct minor diameter for 3/8-24 UNF form tapping, as the required hole diameter differs from conventional cut tap drill sizes. Ensure the workpiece is securely fixtured and use appropriate tapping fluid or cutting oil for the material being tapped. A rigid or synchronous tapping setup is recommended to maintain thread accuracy and prevent tap breakage. Inspect the tap for wear or chipping before each use, and follow all machine shop safety practices when operating drilling and tapping equipment.