Osg 1400136900 Thread Forming Tap 3/8-24 Unf Bottoming Cobalt

Product Description

The OSG 1400136900 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 bright finish, it is engineered for demanding threading applications in tough materials including alloy steel, stainless steel, hardened steel, and carbon steel. The bottoming chamfer of 1 to 1.5 threads allows threading to the bottom of blind holes. With a 3/8-24 UNF thread specification and a Class 3B fit at Thread Limit H5, this tap delivers precise, tight-tolerance threads suited for high-strength fastening applications in production and maintenance environments.

This tap is intended for blind hole threading in ferrous and non-ferrous materials commonly encountered in industrial manufacturing, tooling, and maintenance machining. The right-hand thread direction and UNF thread form make it a standard choice for tapping fine-thread fastener holes in alloy steel, die steel, carbon steel, aluminum, and stainless steel components. It is typically used by machinists, tool and die makers, and maintenance mechanics on drill press, tapping machine, or CNC equipment where controlled feed and speed are maintained. Coolant-through capability is not provided on this tap.

Key Features

• Cobalt high-speed steel construction for heat resistance and durability in hard and abrasive materials
• Bottoming chamfer (1 to 1.5 threads) allows threading close to the bottom of blind holes
• Thread forming design eliminates chips, reducing the risk of chip packing in blind holes
• Class 3B fit at Thread Limit H5 for tight-tolerance thread production
• Right-hand, 3/8-24 UNF thread form suits standard fine-thread fastener applications
• Bright finish with no coolant-through requirement for simplified setups

Compatibility

Designed for threading 3/8-24 UNF blind holes 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 are installed by machinists using a tapping machine, drill press, or CNC machining center with controlled feed rate matched to the thread pitch. The workpiece spindle and power source must be fully stopped before tap changes or manual inspection. Proper tapping fluid or cutting oil appropriate for the workpiece material should be applied to reduce tap wear and ensure accurate thread form. Follow shop-specific tooling procedures and applicable OSHA machine guarding requirements when operating tapping equipment.