Balax 17662-010 Thread Forming Sti Tap M3x0.5 Bottoming Hss

Product Description

The BALAX 17662-010 is a thread forming STI tap designed for M3 x 0.5 metric coarse internal threads in spark-eroded or STI-insert applications. Built from high-speed steel with a bright uncoated finish, this bottoming tap generates threads by cold-forming the material rather than cutting it, producing strong threads with no chips. The D2 thread limit, 2.125 inch overall length, and 0.75 inch thread length make it suited for close-tolerance work in shallow or blind holes. Machinists and maintenance technicians use it where Heli-Coil or similar threaded insert systems are required.

This tap is used in metalworking and maintenance repair operations where M3 x 0.5 STI threads are needed to accept metric threaded inserts. The bottoming chamfer allows threading to the bottom of blind holes, making it appropriate for tight assemblies with minimal thread runout. It fits standard tap handles and machine holders sized for its 0.168 inch shank diameter. Typical applications include aerospace components, automotive assemblies, and precision machine repair where parent-thread restoration using inserts is specified.

Key Features

• Thread forming design produces chip-free M3 x 0.5 metric coarse STI threads
• Bottoming chamfer enables threading close to the bottom of blind holes
• High-speed steel construction for durability across a range of workpiece materials
• D2 thread limit for controlled fit with STI threaded inserts
• Bright uncoated finish suitable for use with standard tapping fluids
• 75 percent thread drill size of 0.133 inches for proper hole prep

Compatibility

Designed for use in STI thread insert applications requiring M3 x 0.5 metric coarse internal threads. Compatible with tap handles and holders accepting a 0.168 inch round shank with a 0.131 inch square drive.

Installation Notes

This tap should be installed by a qualified machinist or maintenance technician familiar with thread forming operations. Ensure the workpiece is secured and the pilot hole is drilled to the specified 75 percent thread drill size of 0.133 inches before tapping. Use an appropriate cutting or tapping fluid to reduce heat and extend tap life. Always back the tap out periodically during the operation to relieve forming pressure in deep holes.