Osg 1805700 Sti Hand Tap 10-24 Unc H2 3 Flute

Product Description

The OSG 1805700 is a hand STI tap designed for cutting screw thread inserts in 10-24 UNC threaded holes. It features a bottoming chamfer, making it suited for threading close to the bottom of blind holes where a plug or taper tap cannot reach. Built from high-speed steel with a bright uncoated finish, this tap operates in H2 thread limit tolerance and produces a 3-flute cutting geometry that supports chip evacuation during hand tapping operations. The 7/8 inch thread length and 2-3/8 inch overall length make it a compact tool appropriate for production and repair threading work performed by machinists and maintenance technicians.

This tap is intended for STI (Screw Thread Insert) applications, where the tapped hole is oversized to accept a helical wire or solid insert that restores the thread to standard dimensions. It is suited for use in aluminum, carbon steel, cast iron, and hardened steel workpieces. Typical applications include thread repair on stripped fastener holes, new-thread production in insert-critical assemblies, and maintenance work across industrial, automotive, and mechanical fabrication environments. This is a single-piece packaged unit intended for bench or hand-tool use rather than machine tapping.

Key Features

• Bottoming chamfer allows threading to the bottom of blind holes
• H2 thread limit for controlled tolerance in STI thread applications
• 3-flute design supports chip flow during hand tapping
• High-speed steel construction handles aluminum, carbon steel, cast iron, and hardened steel
• Bright uncoated finish - no coating buildup to affect dimensional accuracy
• Compact 2-3/8 inch overall length suits confined or shallow workpiece access

Compatibility

Designed for use in STI thread insert applications requiring a 10-24 UNC thread form. Compatible with aluminum, carbon steel, cast iron, and hardened steel workpieces as stated in manufacturer data.

Installation Notes

This tap is installed by hand using a tap wrench; do not use with power tapping equipment unless the tool is specifically rated for machine use. Secure the workpiece firmly before tapping, apply appropriate cutting fluid for the workpiece material, and back off the tap periodically to break chips and prevent binding. Verify the pilot hole diameter matches the STI tap drill size for 10-24 UNC before starting. Follow standard shop safety practices including eye protection when tapping.