Hardened tool steel is unforgiving. Once a part is heat-treated, every remaining operation has to remove material without introducing stress, taper or a recast layer that will fail in service. That is the job of our EDM cell.
Wire EDM: the final geometry
Our Sodick wire EDM machines cut hardened inserts, slides and punch profiles after heat treatment. Positional accuracy is held to ±0.003 mm, with multiple passes used to control surface finish and the recast layer on critical edges.
For parts with a complex profile, wire EDM is often faster and more predictable than milling after hardening. It also lets us use a single setup for both the cavity insert and its matching slide — which is exactly where tolerance stack-up matters.
Electrode management
Sinker EDM is only as good as its electrodes. We track electrode material, wear compensation and the number of burns per electrode. For deep ribs and sharp corners, we use copper-tungsten or graphite grades selected for the detail and the steel being cut.
Measurement is part of the process
Parts are not measured only at the end. Critical dimensions are checked after rough machining, after heat treatment and after EDM. If a dimension is drifting, we correct it before the next operation rather than discovering it at final inspection.
The goal is not to cut fast. It is to cut predictably — so the second part is the same as the first, and the hundredth is the same as the second.
That discipline is what allows us to quote tight tolerances on hardened components and hold them in production, not just in a one-off sample.