Heli-coil 4763-3 Spiral Point Sti Tap M3x0.5 Metric Coarse

Product Description

The HELI-COIL 4763-3 is a spiral point STI tap designed for cutting threads in pre-drilled holes to accept Heli-Coil thread inserts. Built from high-speed steel with a bright, uncoated finish, this plug chamfer tap is engineered for STI Metric Coarse threading at M3x0.5. It features 2 flutes and a spiral point geometry that pushes chips forward, making it well suited for through-hole tapping operations. With an overall length of 2 inches and a thread length of 11/16 inches, it fits standard tap handles and machine setups used in precision repair and manufacturing work.

This tap is used in applications where standard threads have been stripped or damaged and require repair using a Heli-Coil wire thread insert. Typical install scenarios include engine components, aluminum housings, cast components, and other assemblies where M3x0.5 metric coarse internal threads need to be recut to the STI oversize specification. It is used by machinists, maintenance technicians, and field repair professionals working on light-duty threaded fastener repairs.

Key Features

• STI Metric Coarse thread form sized for Heli-Coil thread insert installation
• High-speed steel construction for durability across steel, aluminum, and similar materials
• Plug chamfer provides a balance between ease of starting and thread engagement depth
• Spiral point geometry pushes chips forward, reducing clogging in through-hole applications
• 2-flute design suited for smaller diameter tapping with adequate chip clearance
• Bright, uncoated finish suitable for use with cutting fluids on a wide range of materials

Compatibility

Designed for use with Heli-Coil STI thread insert systems requiring an M3x0.5 Metric Coarse oversize tapped hole. Intended for use as part of a complete Heli-Coil thread repair kit or as a standalone replacement tap in that insert series.

Installation Notes

Installation should be performed by a qualified machinist or maintenance technician familiar with thread repair procedures. Secure the workpiece before tapping and use an appropriate cutting fluid to extend tap life and improve thread finish. Apply consistent, even pressure and back off periodically to break chips and prevent tap breakage, especially in blind holes. Follow the Heli-Coil system instructions for correct drill size and tap depth before installing the thread insert.