Osg 7008600 Spiral Point Sti Tap 8-36 Unf Hss

Product Description

The OSG 7008600 is a spiral point STI tap designed to cut 8-36 UNF threads in Helicoil-style thread insert applications. Built from high-speed steel with a bright/uncoated finish, it features a plug chamfer and a 2-flute spiral point geometry that pushes chips forward ahead of the cut, reducing clog risk in through-hole tapping operations. The overall length is 2.382 inches with a thread length of 0.511 inches and a shank diameter of 0.22 inches. Thread limit is H2, making it well-suited for standard tolerance STI thread insert installations. Machinists, maintenance technicians, and tool-and-die professionals use this tap where thread repair or insert installation is required.

This tap is used in applications where a Helicoil or similar wire thread insert is being installed to repair damaged threads or to create reinforced threads in softer base materials. The 8-36 UNF thread form and STI profile produce an oversized pilot thread that accepts standard 8-36 wire thread inserts. It is appropriate for use in both manual tapping operations and low-speed machine tapping setups. The Helicoil reference number for this tap is 2FSA, and it belongs to OSG Series 125.

Key Features

• Spiral point geometry pushes chips forward, reducing packing in through-hole applications
• High-speed steel construction provides toughness across a range of workpiece materials
• Plug chamfer provides gradual thread engagement suitable for through-hole tapping
• H2 thread limit ensures consistent tolerance for standard STI insert fitment
• Bright/uncoated finish allows visual wear inspection during service
• Helicoil reference number 2FSA for direct cross-reference to insert system requirements

Compatibility

Designed for use with Helicoil-style wire thread insert systems requiring an 8-36 UNF STI thread form. Helicoil reference number 2FSA. Compatible with standard H2 tolerance insert installation tooling.

Installation Notes

Install by a qualified machinist or maintenance technician following the thread insert manufacturer's procedure for STI tapping. Power down or disengage all equipment before tapping threaded holes in assemblies. Use appropriate cutting fluid for the base material to extend tap life and maintain thread quality. Do not force the tap if resistance increases unexpectedly, as this may indicate chip packing or misalignment.