Technical Reference
Wire EDM Corner Radius Guide Technical Reference
A Wire EDM internal corner always retains a radius approximately equal to wire radius plus the discharge gap; external corners can approach sharp. Wire EDM corner radius cannot be smaller than the wire radius plus the discharge gap and path compensation.
Quick Answer
A Wire EDM internal corner always retains a radius approximately equal to wire radius plus the discharge gap; external corners can approach sharp.
Key Technical Points
What the Parameter Changes
A zero-radius internal corner is physically inconsistent with a round wire and spark gap. The consequence changes fit, function, or service performance for the Wire EDM Corner Radius decision; it is not only a change in surface appearance.
How to Select It
Dimension the finished internal radius, not the wire diameter, and use corner control, slower feed, and suitable energy where profile accuracy matters. When planning Wire EDM Corner Radius, apply the requirement only to the dimensions and faces that control fit, function, service life, or documented release.
What Can Go Wrong
Wire EDM corner radius cannot be smaller than the wire radius plus the discharge gap and path compensation. Asking for a sharper corner without changing the process creates a geometry conflict, not a tighter tolerance.
Technical Context
A wire or shaped electrode cannot create an infinitely sharp internal corner. In Wire EDM the practical radius is governed by wire radius plus the working gap and path dynamics; in sinker or micro EDM it also depends on electrode corner wear and orbit. This mechanism explains the limits and behavior that matter when planning Wire EDM Corner Radius.
Feature-Size Decision Table
| Condition or input | Why it matters | What must be confirmed |
|---|---|---|
| Electrode or wire size | sets stiffness and contributes to kerf or corner radius | available size, wear, current capacity, breakage risk |
| Spark gap | adds to slot width or cavity offset | material, energy, pass, and machine technology |
| Depth or section height | changes flushing and deflection | aspect ratio, guide spacing, support, and inspection |
| Inspection method | sets the smallest feature that can be released | probe size, optics, magnification, datum, and uncertainty |
Surface Considerations
Inspect entry and exit edges, verticality, wire-break marks, and the functional cut faces. Skim passes can improve texture and size together, so the final offset and datum must match the inspection plan. For Wire EDM Corner Radius, tie the accepted condition to the feature and inspection method named in the drawing.
Wire EDM Corner Radius Drawing and Release Checkpoints
- Identify the controlled feature, material condition, access direction, and functional datum for this Wire EDM Corner Radius decision.
- Separate dimensional requirements from texture, edge, recast, corrosion, fatigue, or post-process acceptance.
- State the inspection method, sampling or first-article requirement, drawing revision, quantity, and any documentation needed for release.
Limits and Better Alternatives
Main Limit
For Wire EDM Corner Radius Guide, a round wire and discharge gap cannot create a true zero-radius internal corner. Corner control improves the result but does not remove the physical radius. When that boundary dominates, use a larger feature, shorter aspect ratio, Sinker or Micro EDM for a different access condition, or redesign the internal corner when the physical limit is not functional.
Consider Another Route When
Use a larger feature, shorter aspect ratio, Sinker or Micro EDM for a different access condition, or redesign the internal corner when the physical limit is not functional.
Practical Next Step
Inspect entry and exit edges, verticality, wire-break marks, and the functional cut faces. Dimension the finished internal radius, not the wire diameter, and use corner control, slower feed, and suitable energy where profile accuracy matters.
What to Remember
A Wire EDM internal corner always retains a radius approximately equal to wire radius plus the discharge gap; external corners can approach sharp. Apply the parameter only to named features with a datum, process stage, and measurement method.
Technical Reference
Use the values as planning references and define the functional requirement on the controlled drawing.
Use This Guide to Prepare Your RFQ
Contact us when your drawing and requirements are ready for review.
- Drawing or part sketch
- Material grade
- Thickness / part size
- Quantity
STEP/STP, DXF, DWG, PDF, IGS/IGES or ZIP.
Confidential drawing review. NDA support available on request.
Frequently Asked Questions
Can Wire EDM make a zero-radius internal corner?
No. Wire radius and spark gap leave a finite internal radius.
Does smaller wire always improve the result?
No. It can reduce stiffness, speed, and stability.
What should be dimensioned?
Specify the finished feature, depth or height, radius, tolerance, and inspection method.
When should another EDM route be used?
Use Sinker or Micro EDM when access or feature scale differs from a normal through profile.