Differences Between Erosion and CNC Milling
What Are EDM and CNC Milling?
CNC milling is a conventional CNC technology that machines metal by removing material using rotating cutting tools.
EDM (Electrical Discharge Machining), on the other hand, is a precision machining method that shapes metal in a non-contact manner by means of electrical discharges.
In summary: CNC milling is based on mechanical cutting, whereas EDM relies on electrical erosion.
Key Differences in Working Principles
How Does CNC Milling Work?
- Uses rotating cutting tools
- Involves physical contact
- Material is removed as chips
- Tool wear occurs
How Does EDM Work?
- Electrical sparks are generated using a wire or electrode
- No physical contact with the workpiece
- Metal is eroded at micron level
- Material hardness is not a limitation for machining
Related content: You can find detailed information about the working principle of CNC EDM machines.
Which Method Is More Suitable for Which Materials?
| Material Type | CNC Milling | EDM |
|---|---|---|
| Soft Metals | Very suitable | Suitable |
| Hardened Steel | Limited | Very suitable |
| Carbide | Difficult | Very suitable |
| Non-conductive Materials | Suitable | Not suitable |
EDM works only on electrically conductive materials; CNC milling offers a wider material range in this respect.
Comparison of Precision and Surface Quality
- CNC milling provides high precision but is limited by cutting tool geometry
- EDM enables micron-level tolerances and extremely smooth surface finishes
For this reason, EDM is preferred in mold making and precision part manufacturing.
Complex Geometry and Internal Details
- CNC milling is ideal for open surfaces and general geometries
- EDM offers advantages for closed cavities, sharp corners, and complex contours
Related category: Sinker EDM machines deliver superior results in mold cavity details.
Production Speed and Cost Comparison
- CNC milling is faster in mass production
- EDM is slower in terms of processing time but offers superior precision
Therefore, the two methods are often used together.
When Should CNC Milling Be Preferred?
- General machining operations
- Open surfaces and pocket machining
- High-volume serial production
When Should EDM Be Preferred?
- Hardened and difficult-to-machine metals
- Complex and high-precision geometries
- Mold and precision part manufacturing
Related product group: Wire EDM cutting machines are used for high-precision contour cutting.
Can CNC Milling and EDM Be Used Together?
Yes. In modern manufacturing facilities, CNC milling and EDM machines are used as complementary technologies. Rough machining is performed by milling, while precision details are completed using EDM.
EDM and CNC milling solutions can be evaluated together to determine the most suitable method for your production needs.
Let’s determine the right CNC solution for your production together
Technical reference: For a comparison of CNC milling and EDM, see Wikipedia – CNC