Osg 6002700 Hand Sti Tap 2-56 Unc H2 Bottoming

Product Description

The OSG 6002700 is a hand STI tap designed for cutting Screw Thread Insert (STI) threads in a 2-56 UNC configuration. It features a bottoming chamfer for threading close to the bottom of a blind hole, making it the go-to choice when full thread depth near the hole floor is required. Built from high speed steel with a bright finish, this tap runs 3 flutes and carries an H2 thread limit for close-tolerance work. Overall length is 1.75 inches with a thread length of 0.4375 inches and a shank diameter of 0.141 inches. Machinists, tool and die makers, and maintenance technicians install this tap by hand or with a tap handle in light- to medium-duty threading applications.

This tap is suited for STI thread repair and new thread installation in materials including aluminum, carbon steel, cast iron, and hardened steel. The bottoming chamfer design allows threading into blind holes where a plug or taper tap cannot reach full depth. Typical applications include restoring stripped threads using helical insert systems in both production and field-repair environments.

Key Features

• 2-56 UNC thread form with H2 thread limit for controlled tolerance
• Bottoming chamfer enables full-depth threading in blind holes
• 3-flute geometry supports chip evacuation in a range of metals
• High speed steel construction handles aluminum, carbon steel, cast iron, and hardened steel
• Bright finish with no coating for straightforward inspection and re-sharpening
• Compact 1.75-inch overall length suits tight-access work

Compatibility

Designed for use with standard STI thread insert systems requiring a 2-56 UNC H2 tap in bottoming chamfer configuration. Compatible materials include aluminum, carbon steel, cast iron, and hardened steel per OSG Series 126 specifications.

Installation Notes

Hand STI taps are installed by machinists or maintenance technicians using a standard tap wrench or T-handle tap driver. Before tapping, confirm the pilot hole is drilled to the correct STI tap drill size for the insert system being used. Apply cutting fluid appropriate to the workpiece material to extend tap life and improve thread finish. Back the tap out periodically to break chips, especially in blind holes, to prevent tap breakage.