Osg 1400106500 Thread Forming Tap 4-48 Unf Cobalt

Product Description

The OSG 1400106500 is a thread forming tap designed for creating internal UNF threads without cutting, using material displacement to produce stronger threads with no chips. Built from cobalt high-speed steel with a bright finish, this tap handles the 4-48 UNF thread form and is optimized for blind hole threading applications. The modified bottoming chamfer with 2 to 2.5 chamfered threads allows the tap to reach near the bottom of a blind hole. With an H3 thread limit and Class 3B fit, it meets tight tolerance requirements common in precision assemblies. Licensed HVAC, plumbing, and mechanical trades as well as machining professionals will find this tap suited to production and repair work alike.

This tap is intended for blind hole threading in a range of metallic workpiece materials including alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel. The thread forming action, rather than cutting, reduces tap breakage risk in tough materials and produces a work-hardened thread form. It is well suited to CNC tapping centers and manual tapping operations where chip evacuation is a concern. The 4-48 UNF designation makes it appropriate for small-fastener applications in precision components, instrument assemblies, and tight-clearance hardware.

Key Features

• Thread forming design eliminates chips, reducing breakage risk in blind holes
• Cobalt high-speed steel construction for performance in hardened and stainless steel
• Modified bottoming chamfer allows threading close to the bottom of blind holes
• H3 thread limit with Class 3B fit for tight-tolerance precision assemblies
• Right-hand thread direction, compatible with standard tapping equipment
• No coolant-through requirement, suitable for conventional tapping setups

Compatibility

Designed for blind hole threading in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces per Material Application Codes P and N. Part of the OSG HY-PRO NRT Series 14001.

Installation Notes

Thread forming taps require a specific tap drill size larger than a standard cut-tap drill to allow material displacement — verify the correct tap drill diameter for 4-48 UNF forming before drilling. Apply an appropriate tapping fluid or cutting oil for the workpiece material before tapping. Ensure the workpiece is securely fixtured and the tap is aligned perpendicular to the hole to prevent tap breakage. Follow applicable shop safety practices and machine guarding requirements when operating tapping equipment.