Accelerating Production of Hardened Tool Steel Cable Crimping Dies Using EDM Wire Erosion and Precision Assembly
The Challenge
A manufacturer supplying cable termination equipment to the energy and industrial sectors approached Strategic Innovations Dundee Ltd with a tooling challenge involving a family of interchangeable crimping dies.
The dies were manufactured from hardened D2 tool steel at 58–60 HRC and featured intricate crimping profiles, narrow internal radii, and multiple precision alignment features. Several profile sections measured less than 0.5mm in width, making conventional milling methods unsuitable due to cutter access limitations and excessive tool wear.
The customer’s existing supplier was machining the profiles before heat treatment, which frequently resulted in dimensional movement during hardening. Additional grinding operations were required to recover tolerance, increasing both cost and lead time.
The project required a manufacturing process capable of maintaining dimensional consistency across multiple die variants while reducing production bottlenecks and improving repeatability for future batch orders.
Target tolerances included profile accuracy within ±0.01mm and surface finish requirements suitable for repeated crimping operations without premature tool wear.
The Engineered Solution
Following a detailed engineering review, Strategic Innovations developed a manufacturing route combining CNC machining, EDM wire erosion Scotland capabilities, surface finishing, and final assembly operations.
The process began with CNC milling of pre-hardened D2 steel blanks. Datum locations, mounting features, and non-critical geometry were completed prior to EDM operations.
Because of the material hardness and complex profile requirements, wire EDM was selected as the primary finishing process.
The engineering team generated optimized EDM cutting strategies that enabled:
Multiple skim passes were programmed following the rough-cut operation to achieve the required dimensional accuracy and edge quality.
Critical crimping profiles were machined using fine-wire technology, allowing intricate geometry to be produced with exceptional consistency. The EDM process also eliminated concerns regarding tool deflection and cutter wear commonly associated with machining hardened steels.
Following wire erosion, components underwent controlled polishing and surface finishing operations. Functional contact surfaces achieved Ra values between 0.4µm and 0.7µm, ensuring smooth crimp formation and minimizing wear during repeated production cycles.
Laser marking was applied for tool identification and inventory control.
To further streamline customer operations, Strategic Innovations provided complete sub-assembly engineering, including installation of guide pins, alignment bushes, retention hardware, and final fit verification.
This integrated manufacturing approach allowed the customer to receive fully assembled tooling sets ready for immediate installation on production equipment.
The Outcome & Operational Impact
The completed project delivered significant improvements across manufacturing efficiency, tooling performance, and supply chain management.
Key outcomes included:
The project demonstrated how specialist precision engineering Dundee expertise can overcome the challenges associated with hardened materials and highly detailed tooling geometries.
By combining advanced CNC machining Scotland capabilities with EDM technology and assembly services, Strategic Innovations provided a robust solution that enhanced productivity while reducing operational complexity.
For customers seeking dependable subcontract manufacturing UK support, the ability to consolidate machining, finishing, marking, and assembly within a single facility continues to generate measurable commercial value.
Have a complex engineering component or production bottleneck? Send your technical specifications and RFQ straight to the engineering team at Strategic Innovations Dundee Ltd (https://www.strategic-innovations.co.uk) for a comprehensive manufacturing evaluation.
