What accuracy can production wire EDM hold?

At Boyang Hardware, wire EDM routinely holds ±0.005 mm on production features, with 0.001 mm achievable on selected critical dimensions through skim passes and controlled setup. Multiple skim cuts progressively refine the profile and surface finish, so a rough-cut edge can be re-traced to tighter tolerance without re-fixturing the part.

When should I choose wire EDM instead of CNC milling for a profile?

Four situations: the material is hardened beyond easy cutting (above roughly 50 HRC); the profile needs sharp internal corners a round end mill cannot leave; the workpiece is thin or delicate and would deflect under milling forces; or the part must leave the machine burr-free and stress-relieved. Wire EDM applies only electro-thermal erosion — no cutting force touches the part.

Does wire EDM work on aluminium, plastics or non-conductive materials?

No. The spark discharge requires an electrically conductive workpiece, so wire EDM works on steels, hardened tool steels, copper, brass, aluminium, titanium and carbide, but not on plastics, ceramics or other insulators. Non-conductive parts stay on the CNC milling route — see the materials guide.

Production Wire EDM Services: ±0.005 mm Profiles Cut by Spark, Not Force

Boyang Hardware · 7 EDM machines · Zhongshan, Guangdong, China

Direct answer Boyang Hardware operates 7 EDM machines dedicated to production wire EDM within a 54-machine-tool facility in Zhongshan, China. Wire EDM cuts any electrically conductive material — including fully hardened tool steel, carbide and titanium — holding ±0.005 mm on production features and down to 0.001 mm on selected critical dimensions via skim passes. Because erosion is electro-thermal, there is no cutting force: thin walls, delicate blanks and sharp internal corners come off the machine burr-free, with an edge condition no end mill can match.

7EDM machines on site
±0.005 mmproduction accuracy
0.001 mmcritical dimensions
54machine tools total
100%CMM inspection
1–2 daysquotation

Wire EDM vs CNC milling — when the spark route wins

Table 1 — Decision factors between wire EDM and milling for profile work. Most real jobs use both: milled to near-net, EDM for the critical profile.
Factor	Wire EDM	CNC milling
Hardened material (>50 HRC)	Cuts freely, hardness irrelevant	Difficult to impossible; needs grinding instead
Sharp internal corners	Corner radius = wire radius (~0.1–0.25 mm)	Corner radius = end-mill radius, usually much larger
Cutting force on part	None — erosion only	Significant; deflects thin or delicate work
Burr condition	Burr-free or minimal	Burrs; deburring step required
Through-thickness depth	Unlimited within machine height	Deep narrow slots impractical
Speed on soft alloys, simple shapes	Slower per mm² removed	Much faster — always prefer milling there
Taper / draft angles	Yes, on tapered-wire machines	Yes, with contouring capability

What wire EDM actually does to the material

A continuously fed brass wire carries pulsed electrical discharges in deionised water; each spark melts a micro-dot of the workpiece, and the flushing flow carries the debris away. Nothing mechanical touches the part, so no clamping force resists the cut and no tool pressure bends the work. Heat-affected depth is small — a few microns per pass — and repeated skim cuts over the same path both remove that layer and progressively improve accuracy from the rough pass to the ±0.005 mm production window, and to 0.001 mm on dimensions you mark critical.

Two practical consequences buyers care about: profiles cut from pre-hardened or through-hardened steel come out dimensionally true because the material has no stresses left to move after hardening; and thin serrated or slotted parts that would chatter under a mill leave the wire machine flat and unmarked. Complementary capability: 6 grinding machines handle hardened flat and cylindrical finishing — see how critical tolerances are achieved.

Typical production work on our EDM line

Table 2 — Representative production categories. Materials: hardened tool steels, carbide, stainless, copper, brass, aluminium and titanium (all conductive).
Category	Why wire EDM suits it	Typical feature tolerance
Stamping and progressive-die inserts	Hardened tool steel, sharp corners, precise die clearances	±0.005 mm; 0.001 mm on clearance-critical edges
Mould components and gate inserts	Hardened steel profiles with fine detail	±0.005 mm
Extrusion and form dies	Complex constant profiles through thick plate	±0.005 mm with taper
Precision slots and windows in production parts	Burr-free, no distortion in thin sections	±0.005 mm
Carbide and conductive-ceramic-bonded parts	Conventional cutting impractical	±0.005 mm; skim cuts for critical fits

The same facility machines the surrounding components — milled bodies, turned cores, stamped blanks — so a wire-cut insert and its mating block ship as one inspected set, measured 100% on the 3D CMM. EDM-cut dies pair with our 100% inspection workflow, and non-conductive geometry stays on the 5-axis milling route.

Running wire EDM for production, not just samples

Seven machines mean scheduling redundancy: a repeat order is not queued behind a single tool, and a fixture established on the first batch is reproduced on subsequent runs. Production batches run alongside the milling, turning, die casting, injection moulding and stamping operations of the wider plant, so EDM-cut components slot into a larger assembly programme without a second supplier. Quotations for wire EDM work are returned in 1–2 working days, with the skim-pass count and accuracy confirmation stated explicitly rather than assumed.

Honest limits: wire EDM is slow and comparative in cost — a simple aluminium bracket is cheaper milled, and quoting EDM for soft-material bulk removal would inflate your price for no benefit. Only conductive materials qualify; starting holes are needed for closed internal profiles (drilled or EDM-drilled first, leaving a small witness); wire-taper angle has practical limits; and very large bed sizes are constrained by machine travel — dimensions beyond our work envelope are declared at quotation, not discovered later.

FAQs

How much heat distortion or recast layer should I expect?

Minimal and managed: the heat-affected depth per cut is a few microns, and the standard skim passes remove the recast layer on critical edges. For wear surfaces that cannot tolerate any recast, the finishing pass is followed by grinding — see the tolerance route above.

Can you EDM an existing part that is already hardened?

Yes — that is a core wire EDM use case. Hardened dies, broken fastener removal windows and post-hardening slots are routine, with hardness stated on the drawing so the wire feed and skim strategy are set correctly.

What inspection evidence comes with wire EDM parts?

100% dimensional inspection against the drawing on the 3D CMM with a report shipped alongside, plus material certificates for the stock used and finish certificates where grinding or coating follows.