How to find an EDM machining supplier in China.
EDM is not one process. Wire EDM, sinker EDM, and EDM hole drilling involve different equipment, programming, flushing, electrode or wire choices, surface conditions, and inspection questions. The right supplier search starts by defining the result your part needs.
Wire EDM, sinker EDM, and hole drilling solve different problems.
A supplier that is strong in one EDM process may not be the best fit for another. Name the feature, material, tolerance, surface condition, and production purpose before comparing shops.
Profile and through-feature work
Useful for conductive materials and precise profiles, slots, punches, dies, and features that can be reached with a wire path.
- Ask about taper control, corner strategy, wire diameter, and flushing
- Define recast layer, surface finish, and skim-cut expectations
- Confirm workpiece size, submerged or non-submerged process, and inspection method
Formed cavities and blind features
Uses an electrode to erode a cavity or feature where a wire path cannot reach, with electrode design and flushing central to the result.
- Clarify electrode material, wear compensation, and electrode inspection
- Review corner radius, surface finish, and recast or heat-affected condition
- Ask whether electrode manufacture is in-house or subcontracted
Small starting holes
Small-hole EDM can support wire-starting, cooling passages, and difficult conductive materials where conventional drilling is unsuitable.
- Define hole diameter, depth, straightness, and location tolerance
- Ask how flushing and electrode wear are controlled
- Confirm inspection access for deep or angled holes
EDM quotes improve when the surface condition is specified.
“EDM tolerance” is not a complete requirement. The buyer should clarify the final surface condition, the number of finishing passes, whether recast or affected material is acceptable, and how the feature will be measured.
- Material grade, hardness, heat treatment, and conductivity
- Feature geometry, thickness, depth, taper, corner radius, and access
- Dimensional tolerance, positional relationship, surface finish, and edge condition
- Requirement for skim cuts, polishing, lapping, or downstream finishing
- Quantity, repeatability, inspection report, and delivery country
Ask who controls the electrode or wire path.
For sinker EDM, electrode design and wear compensation can determine whether the cavity matches the drawing. For wire EDM, programming, taper compensation, flushing, and skim-pass planning affect the result.
Evidence to request: a redacted inspection report or comparable sample that shows how the supplier measures the finished feature.
What to verify before releasing a precision EDM job.
| Area | What to ask |
|---|---|
| Machine | Make, model, travel, maximum workpiece, dielectric system, wire or electrode range, and machine condition. |
| Programming | CAM or control system, taper strategy, electrode design, simulation, revision control, and who approves the NC program. |
| Process | Flushing, filtration, wire or electrode wear, skim passes, thermal control, surface condition, and setup repeatability. |
| Inspection | How profile, hole size, taper, location, corner radius, surface finish, and recast condition are checked. |
| Subcontracting | Whether heat treatment, polishing, coating, inspection, or electrode manufacture is performed outside the shop and how records are linked. |
| Production | First-article process, batch consistency, nonconformance handling, traceability, packaging, and communication at revision changes. |
Have an EDM feature that needs a capable supplier?
Share the material, feature geometry, tolerance, finish, quantity, and inspection requirement. The more precisely the EDM result is described, the more useful the supplier search becomes.