Osg 34200108 Spiral Point Sti Tap M2 X 0.4 2 Flutes

Product Description

The OSG 34200108 is a spiral point STI tap designed for cutting internal STI (Screw Thread Insert) metric coarse threads in a variety of materials. Built from vanadium high-speed steel with a V finish, this plug-chamfer tap is engineered for through-hole tapping applications where chip evacuation is critical. It produces M2 x 0.4 threads to a 6H class of fit with a D2 thread limit, making it suitable for precision work in manufacturing, maintenance, and repair environments. The 2-flute spiral point geometry pushes chips ahead of the tap to keep flutes clear during the cut. Licensed machinists, tool-and-die makers, and MRO technicians are the primary users.

This tap is used to prepare holes for Heli-Coil-style STI inserts in applications where a standard M2 x 0.4 thread has been stripped or where enhanced thread strength is required from the start. The plug chamfer makes it well-suited for through-hole setups where the tap can pass through the workpiece. Its compact overall length of 1-7/8 inches and 9/16 inch thread length make it appropriate for small workpieces and tight clearance situations common in precision assembly and repair work across aerospace, automotive, and general metalworking.

Key Features

• M2 x 0.4 STI metric coarse thread form for tapping holes that accept screw thread inserts
• Vanadium high-speed steel construction for improved wear resistance and edge retention
• V finish provides a smooth cutting surface suitable for a range of metals
• Plug chamfer (3-5 threads) enables clean entry in through-hole applications
• 2-flute spiral point geometry pushes chips forward to reduce clogging
• 6H class of fit with D2 thread limit for consistent, tolerance-controlled thread production

Compatibility

Designed for use in through-hole tapping operations requiring STI metric coarse M2 x 0.4 threads per the Series 342STI specification. Intended for use with standard STI insert installation tooling and compatible M2 STI Heli-Coil-style insert systems.

Installation Notes

This tap is intended for use by machinists and trained metalworking professionals. Always ensure the workpiece is securely clamped and that the correct STI drill size has been used to prepare the hole before tapping. Apply appropriate cutting fluid for the workpiece material to reduce heat and extend tap life. Back the tap out periodically to break chips and reduce torque buildup, even though the spiral point geometry assists with chip evacuation in through-hole operations.