STI Taps: How to Prepare the Material for Screw Thread Inserts
Using the correct tap is critical when installing a screw thread insert. STI taps (Screw Thread Insert taps) are specifically designed to create the proper tapped threads required for helical wire inserts like E-Z LOK® coil inserts.
Unlike standard taps, STI taps account for the insert’s larger outside diameter while maintaining the correct internal thread size after installation.
E-Z LOK offers high-quality STI taps and installation tools designed to ensure:
- Accurate thread size
- Reliable insert installation
- Long-term fastener performance
- Consistent results across a wide range of materials
What Are STI Taps?
STI taps, or Screw Thread Insert taps, are precision cutting tools used to create threads sized specifically for screw thread inserts.
A standard tap cuts threads that match the nominal screw size. An STI tap cuts slightly larger threads to accommodate the insert’s external diameter. Once the insert is installed, it restores the internal thread to its original specified size, creating a strong and durable fastening solution.
Key Differences Between STI Taps and Standard Taps
- Designed for use with helical coil inserts
- Create the correct tapped threads for insert installation
- Available in both inch and metric thread sizes
- Offered in multiple thread types
- Engineered for clean cutting and efficient chip removal
Why Use STI Taps?
Using the proper STI tap ensures:
- Correct insert fit and retention
- Accurate final internal thread size
- Reduced risk of installation issues
- Improved performance in metal and softer materials
Whether repairing damaged threads or reinforcing new holes, STI taps are essential for achieving professional results.
Thread Sizes, Class Fit, and Length Options
E-Z LOK STI taps are available in a wide range of thread sizes, including both inch and metric configurations. Selecting the correct class fit (such as 2B or 3B) ensures compatibility with your fasteners and performance requirements.
Available Options Include:
- UNC, UNF, and metric thread types
- Standard and specialized geometries
Choosing the proper thread class and size ensures that the installed insert distributes load evenly and provides secure holding strength.
Materials and Cutting Performance
STI taps are used in a variety of materials, including:
- Aluminum
- Steel
- Stainless steel
- Other common industrial metals
Because inserts are often used to reinforce threads in softer materials like aluminum, the tap must produce precise threads with minimal burr formation. Proper cutting performance also improves chip control, helping create clean tapped threads and reducing rework.
Using high-quality tools ensures smoother cutting and consistent thread formation for insert installation.
STI Taps for Thread Repair and Reinforcement
Thread repair is one of the most common applications for STI taps. When threads in metal components become stripped or worn, installing a helical insert restores strength and functionality.
Typical Installation Process
- Drill the damaged hole to the recommended size
- Tap the hole using the correct STI tap
- Install the screw thread insert
- Break off the tang (if applicable)
- Install the fastener
This process produces durable threads that often exceed the strength of the original material.
Inch and Metric Options
E-Z LOK offers STI taps in both inch and metric thread standards to meet global application requirements.
When selecting the correct tap, verify:
- Thread size
- Thread pitch
Proper selection ensures the final internal thread meets fastener specifications.
STI Taps and Installation Tools
Successful insert installation requires using the proper tools in addition to the correct STI tap. E-Z LOK offers a complete range of installation solutions for:
- Manual installations
- Production environments
- Maintenance and repair applications
Combining high-quality STI taps with compatible installation tools ensures consistent and repeatable results.
How to Choose the Right STI Tap
When selecting an STI tap, consider:
- The type of screw thread insert being used
- Required internal thread size
- The material being tapped
If you are unsure which STI tap is right for your application, E-Z LOK can help guide you to the correct size and type.
Why Choose E-Z LOK for STI Taps?
E-Z LOK specializes in threaded insert solutions and related tools. Our STI taps are designed to:
- Deliver clean, precise cutting
- Ensure proper insert fit
- Support long-term fastener reliability
- Meet industry standards
With properly engineered STI taps and installation tools, customers can create strong, long-lasting threads in a wide range of metals while improving efficiency and minimizing downtime.
Explore the full range of E-Z LOK threaded insert solutions to learn more about STI taps, screw thread inserts, and compatible tools designed to meet your specific application needs.