3D modelling for wire EDM and CNC requires precision. Even a minor error in CAD can lead to incorrect cutting, higher costs and the need for rework. Here are the 7 most common problems and how to avoid them.
⚙️ Common 3D Modelling Problems
1. Open Geometry
Lines or surfaces not closed — PEPS CAM cannot generate a correct tool path. Solution: check the model before export, use CAD tools to detect open edges.
2. Duplicate Surfaces or Lines
Double elements extend cutting time and cause CAM errors. Solution: careful layer control and removing duplicates in the CAD editor.
3. Overly Complex Geometry
Many tiny details → long EDM time, difficulty maintaining tolerances. Solution: simplify without losing functionality, eliminate unnecessary features.
4. Wrong Units
mm vs inches → wrong dimensions on the finished part. Solution: set units at the start of the project and verify exported files.
5. Missing Tolerances
No specified deviations → incorrect part fit in assembly. Solution: apply ISO-compliant tolerances, mark critical dimensions.
6. Sharp Corners and Narrow Slots
A problem for the wire electrode — longer cutting time, risk of part damage at extreme features. Solution: radius corners where the function allows, minimise narrow slots.
7. Unclear Model Structure
No layer naming, no organisation → difficulty for the EDM operator preparing the CAM file. Solution: clear layer structure and logical component names.
🧩 Best Practices for CAD Designers
- Create parametric models in SolidWorks or MegaCAD — easy to modify
- Use closed contours and surfaces — an absolute requirement for PEPS CAM
- Simplify geometry — fewer details = lower wire EDM cost
- Check units and scale before every export
- Consult the wire EDM operator — practical advice is invaluable
💡 Tips for Customers Ordering Wire EDM
- Always provide complete source data — CAD file, material, tolerances
- If the part is old — consider 3D scanning + reverse engineering
- Don't hesitate to ask the supplier to verify the file before production