Process & Material
Gold Sinker EDM Feasibility Review
Gold can be machined with Sinker EDM when the geometry matches blind cavities, ribs, shaped pockets, mold details, deep forms, and internal geometry that a traveling wire cannot reach. Gold is a very soft, dense and highly conductive precious metal; the supplied condition affects support, discharge energy, finishing, and inspection.
Quick Answer
Sinker EDM is suitable for Gold when the feature is a blind cavity, rib, pocket, or internal form that a shaped electrode can reach from one side. The supplied condition must be stated before tolerance and surface requirements are confirmed.
Key Material Decisions
How This Material Behaves
A very soft, dense and highly conductive precious metal. In Sinker EDM, the supplied condition changes electrode wear, cavity-floor consistency, corner growth, and the finishing strategy—especially on deep ribs and textured surfaces.
Choosing the Right Condition
Choose Sinker EDM for blind cavities, ribs, shaped pockets, mold details, deep forms, and internal geometry that a traveling wire cannot reach. State the exact Gold condition, then set tolerance, finish, support, and inspection from the controlled feature rather than the whole part.
Risks to Manage
For Sinker EDM, surface marking, thin-feature distortion and material recovery can matter more than discharge stability. Orbit, local heating and electrode wear can shift wall size while dishing the floor during repeated burns on the same wall, floor and corner system; acceptance must focus on high-value edges, recovered slugs and mark-sensitive surfaces. On Gold, the resulting defect can be corner overburn, fixture marking or unnecessary removal from a high-value cavity. For Gold, use protected fixturing, minimize unnecessary stock removal and maintain a controlled recovery and handling procedure. Compare the roughing electrode, finish electrode and final cavity rather than relying on nominal electrode size; document geometry, handling marks, material loss and recovery records for Gold.
How Sinker EDM Works on Gold
Sinker EDM reproduces a shaped electrode as a blind cavity in Gold. Electrode material, wear, orbit, pulse energy and debris evacuation control wall size, floor depth, corner definition and surface condition. Where final size or texture is critical, roughing and finishing electrodes should be planned as separate operations.
Sinker EDM Capability Reference
| What you're asking | What you can expect |
|---|---|
| Feature types | blind cavities, ribs, shaped pockets, mold details, deep forms, and internal geometry that a traveling wire cannot reach |
| Tolerance | ±0.008–0.030 mm |
| Surface finish | Ra 0.2–6.3 μm |
| Electrode choice | Graphite or copper selected from cavity, finish, and wear needs |
| Primary cavity limit | Depth, rib width, access, and debris evacuation |
| Main limitation | Electrode access and debris evacuation limit deep, narrow blind geometry. |
Material Condition Reference
| Condition | What to expect | Watch out for | Surface notes |
|---|---|---|---|
| annealed | Use stable support and economical roughing. | Clamping and material condition can move delicate features. | Apply fine finishing only to functional faces. |
| work-hardened | Balance dimensional stability with feature-specific finishing. | Residual stress can shift thin sections or small details. | Identify wear, seal, fatigue, or contact surfaces. |
| finished or plated condition | Use conservative energy and selective inspection. | Finished or hardened surfaces can be sensitive to edge damage and recast. | Use lower-energy finishing or post-processing where function requires it. |
How This Material Behaves
Gold is extremely soft, dense, conductive, and costly. In EDM, this means the part can be damaged by clamping or handling before spark erosion becomes the limiting factor, and unnecessary overcut directly increases material loss. Use broad nonmarking support, minimize roughing stock, capture the final geometry with few controlled passes, and keep contact-surface cleanliness in the release plan. For Sinker EDM, surface marking, thin-feature distortion and material recovery can matter more than discharge stability. In cavities, fixture protection, electrode compensation and limited roughing allowance are needed to avoid unnecessary material loss or surface marking.
Surface Integrity and Post-Process
For Sinker EDM on Gold, use protected fixturing, controlled finishing and recovery procedures for cut-off material. Use roughing and finishing electrodes separately where cavity size or texture is controlled. Apply polishing, lapping or recast removal only to named functional faces, and inspect wall, floor and corner condition after the final surface operation.
Gold Sinker EDM Checkpoints
- Confirm that the feature matches blind cavities, ribs, shaped pockets, mold details, deep forms, and internal geometry that a traveling wire cannot reach.
- State the supplied condition: annealed, work-hardened, and finished or plated condition.
- Mark the controlled dimensions, functional surfaces, datum scheme, and inspection method.
Typical Parts and Features
- fine contacts
- watch and jewelry details
- laboratory electrodes
- mold cavities
- blind pockets
- deep ribs
Limits and Better Alternatives
Main Limit
Electrode access and debris evacuation limit deep, narrow blind geometry. On Gold, surface marking, thin-feature distortion and material recovery can matter more than discharge stability; the supplied condition still controls support, finishing, and surface-integrity review.
Consider Another Route When
Use Wire EDM for through profiles, CNC machining for open cavities with tool access, or grinding for simple flat precision surfaces.
Practical Next Step
Send the Gold drawing with condition, controlled geometry, tolerance, functional surface callouts, quantity, and inspection requirements. If the route is unclear, we will compare Sinker EDM with the adjacent EDM or conventional process.
Practical Takeaway
Gold is compatible with Sinker EDM when the feature matches the process access. The supplied condition determines support, finishing, surface control, and inspection.
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.
- Process: Sinker EDM
- Material: Gold
- 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.