Sliding Connecting Block: Wire EDM Deep Slot with True 90° Internal Corners, Eliminating Tool Interference

We manufactured a precision sliding connecting block from hardened mold steel for an industrial automation equipment supplier. The component requires deep slots and internal edge slots with true 90° corners — geometries impossible to achieve with standard end mills due to tool radius and shank interference. Using slow wire EDM, we cut these features directly in the hardened state, eliminating the need for EDM electrode burning or multiple setups.

Project Overview

Key Technical Highlights

• True 90° Internal Corners: Wire EDM produced zero-radius internal corners on deep slots, impossible with milling cutters (minimum R0.5–1.0mm). This ensures precise mating with square-edged components.
• Internal Edge Slots (Tool-Accessible): Complex inner-edge slots located deep inside the part were cut in a single wire EDM pass, eliminating secondary operations or custom lollipop cutters.
• Hardened Material Direct Cutting: Wire EDM machined mold steel at 52–58 HRC with no softening pre-treatment, preserving wear resistance for high-cycle automation applications.
• Slot Width Precision: Achieved ±0.005mm slot width consistency over full 45mm depth, ensuring smooth sliding fit without play or binding.

Quality Verification

Each sliding block underwent CMM inspection for slot position, width, and parallelism. Internal corner radii were verified using optical comparator and radius gauge (confirmed true 90°). Sliding surfaces were tested with profilometer (Ra≤0.4μm) and mating part fit-tested on an automation rail system.

Industry Applications

This sliding connecting block is ideal for:
✓ Automated pick-and-place systems
✓ Linear motion assemblies
✓ Precision tool changers
✓ Custom automation slides & guides

Why Partner With Us?

• True 90° internal corners without radius limitation
• Wire EDM of deep slots & tool-inaccessible features
• Direct cutting of hardened mold steel (up to 60 HRC)
• 25+ years of automation component manufacturing