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Case Study

Custom Shear Bolts Solve Supply Chain Challenges with Quality Documentation

When a prime defense contractor needed specialty shear bolts with proper first article inspection reports, HSI stepped in to provide both the parts and the quality documentation required.

CNC MachiningFixture DesignQuality Testing Alloy steel AS9102 FAIDimensional inspection

Meeting aerospace and defense quality requirements isn’t just about manufacturing the right parts—it’s also about providing the proper documentation to prove it. When a prime defense contractor approached Harley & Son with a unique challenge, we demonstrated our commitment to flexibility and customer success.

The Challenge

The customer required specialty shear bolts for a critical application. These weren’t ordinary fasteners—they featured a dual-head design with a countersunk angled head and an external hex head connected by a precision-engineered breakaway section. The thin metal connection is designed to shear at a specific torque level, creating a tamper-evident fastener that becomes essentially unremovable once installed.

The customer had identified a screw manufacturer in the UK who could produce the parts, but there was a significant problem: the supplier was unwilling to provide an AS9102 First Article Inspection Report. For aerospace and defense applications, this documentation isn’t optional—it’s a critical requirement that validates the manufacturing process and ensures parts meet all specifications.

Faced with a choice between compromising their quality requirements or finding a new supplier, the customer reached out to Harley & Son for help.

Our Solution

Understanding the urgency and importance of both the parts and the documentation, our team took immediate action. To ensure the shear bolts would perform exactly as specified, we designed and built a custom test fixture specifically for validating the snap-off torque characteristics. This fixture allowed us to conduct thorough, repeatable testing to determine the precise torque values at which the breakaway section would shear.

Once our testing validated the manufacturing process and confirmed the parts met all requirements, we produced a batch of the specialty shear bolts and provided the complete AS9102 First Article Inspection Report the customer needed to satisfy their quality management system requirements.

The Results

By working with Harley & Son, the customer gained more than just compliant parts:

  • Local Supply Chain: No more dependence on overseas suppliers for critical components
  • Quality Assurance: Full AS9102 documentation meeting aerospace and defense standards
  • Faster Delivery: Shorter lead times with a domestic supplier
  • Responsive Support: Direct access to our engineering team for any future needs

This project exemplifies our commitment to flexibility and customer service. When our customers face challenges—whether it’s a unique part requirement, documentation needs, or supply chain issues—Harley & Son has the capabilities and dedication to find solutions that meet their exacting standards.