Osg 6018300 Hand Sti Tap 3/8-24 Unf H2 Plug Chamfer

Product Description

The OSG 6018300 is a hand STI tap designed for cutting screw-thread inserts in 3/8-24 UNF threads. STI taps cut an oversized thread profile that accepts helical thread inserts, restoring or reinforcing threaded holes in a wide range of base materials. This tap features a 4-flute geometry with a plug chamfer, which starts threading gradually and works well for through-holes. Built from high speed steel with a bright finish, it holds up under repeated use in shop and field applications. The H2 thread limit controls tolerance for a consistent fit with standard inserts. Thread length is 1.25 inches and overall length is 2.9375 inches.

This tap is suited for threading applications in aluminum, carbon steel, cast iron, and hardened steel. It is commonly used by machinists, maintenance technicians, and field service professionals repairing damaged or stripped threads. The plug chamfer and 4-flute design make it a practical choice for production and repair work on through-holes where insert installation is required.

Key Features

• 3/8-24 UNF thread size for fine-pitch STI insert applications
• H2 thread limit for controlled tolerance and consistent insert fit
• Plug chamfer for gradual thread engagement in through-holes
• 4 flutes for efficient chip removal and stable cutting action
• High speed steel construction for durability across multiple materials
• Bright finish with no coating buildup, suitable for a wide range of cutting fluids

Compatibility

Designed for use with helical thread inserts in 3/8-24 UNF applications. Compatible base materials include aluminum, carbon steel, cast iron, and hardened steel.

Installation Notes

STI taps are installed by machinists or maintenance technicians using a standard tap wrench or machine spindle. Always secure the workpiece before tapping and use an appropriate cutting fluid for the base material. Back the tap out periodically to clear chips, especially in deeper holes. Follow applicable shop safety and tooling guidelines for speeds and feeds when using in a machine setup.