Osg 1400124001 Thread Forming Tap 12-28 Unf Cobalt

Product Description

The OSG 1400124001 is a thread forming tap in the HY-PRO NRT series, designed for cold-forming internal threads without cutting. Sized for 12-28 UNF thread, it operates with a modified bottoming chamfer of 2 to 2.5 threads, making it suitable for threading close to the bottom of blind holes. Constructed from cobalt high-speed steel and finished with a steam oxide coating, it is built for durability in demanding tapping applications. The tap carries a Thread Limit of H4 and is configured for right-hand, single-direction threading. Licensed tradespeople and machining professionals working in production or maintenance environments are the typical installers.

This tap is suited for blind hole threading in materials including alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel. Its thread forming design displaces material rather than cutting chips, which reduces the risk of chip accumulation in blind holes and produces stronger thread forms. It fits standard tapping chucks and machine tool holders compatible with the shank and square drive dimensions specified for this series. Typical use cases include precision fastener holes in structural components, tooling fixtures, and fabricated assemblies across both job shop and production environments.

Key Features

• 12-28 UNF thread form produced by cold forming, not cutting, for stronger thread geometry
• Modified bottoming chamfer (2 to 2.5P) allows threading close to the bottom of blind holes
• Cobalt construction improves heat and wear resistance compared to standard HSS taps
• Steam oxide coating reduces friction and provides corrosion resistance during storage and use
• H4 thread limit supports controlled tolerance fitting in precision assemblies
• Right-hand thread direction; no coolant-through feature required for typical applications

Compatibility

Rated for use in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel. Material Application Codes P and N indicate suitability for steel and non-ferrous material groups. Designed for blind hole threading applications in standard machine tapping setups.

Installation Notes

Thread forming taps require a specific drill size matched to the desired thread form percentage; consult a tap drill chart for the correct pilot hole diameter before use. Power down or de-energize any machine tool before changing tooling. Use a tapping fluid or cutting oil appropriate to the workpiece material to extend tap life and maintain thread quality. Always back the tap out carefully after reaching the desired depth to avoid binding in the blind hole.