Process & Material
Pure Tungsten Micro EDM High Precision Tolerance + Fine Finish Review
This Pure Tungsten Micro EDM page combines a High-precision tolerance target with a Fine surface target. These requirements must be planned together because finishing passes improve texture while also changing profile offset, cavity size, hole size, or edge geometry.
Quick Answer
For Pure Tungsten, ±0.005–0.010 mm and Ra 0.8–1.6 μm are achievable on selected Micro EDM features when electrode wear, gap stability, micro-flushing, thermal control, and measurement resolution are planned together. Apply both targets from the same datum, and reserve the tightest values for the dimensions and faces that control function.
Key Quality Decisions
What These Targets Mean
On Pure Tungsten, ±0.005–0.010 mm controls the named dimensions and Ra 0.8–1.6 μm controls the named functional faces. In Micro EDM, electrode wear and measurement resolution can consume the tolerance while low-energy finishing changes edge radius and texture. The supplied condition adds a separate risk: edge chipping and subsurface damage require strong support and low-energy finishing.
Getting Both Targets Right
Use one machining and inspection datum. Apply ±0.005–0.010 mm only to dimensions that control fit, and Ra 0.8–1.6 μm only to functional faces. Plan electrode wear, feature-to-electrode ratio, micro-flushing, aspect ratio, edge radius, thermal stability, and measurement resolution. State the exact Pure Tungsten condition and the inspection method before releasing the result.
What Gets Missed
On a sub-millimeter hole, slot, or pitch feature specified at ±0.005–0.010 mm and Ra 0.8–1.6 μm, electrode wear and measurement uncertainty can consume the remaining tolerance while the edge rounds during finishing. The tolerance represents a small remaining offset allowance, while the finishing pass removes enough stock to change edge radius and local size; treating them as independent callouts can make the last finishing step destroy the dimension it is meant to improve. Inspect size, pitch, depth, edge radius, electrode wear, and measurement uncertainty after the final surface step. For Pure Tungsten, also account for this material-specific risk: edge chipping and subsurface damage require strong support and low-energy finishing.
How the Targets Interact
For Pure Tungsten, ±0.005–0.010 mm and Ra 0.8–1.6 μm are linked through the Micro EDM finishing route. Electrode wear and measurement resolution can consume the tolerance while low-energy finishing changes edge radius and texture. The release plan must bind material condition, geometry, datum, finishing stage, and measurement to the same named features.
Micro EDM Capability Reference
| What you're asking | What you can expect |
|---|---|
| Feature types | micro holes, micro slots, miniature cavities, fine pins, and sub-millimeter precision details |
| Tolerance | ±0.002–0.010 mm |
| Surface finish | Ra 0.1–1.6 μm |
| Feature scale | Sub-millimeter holes, slots, and cavities |
| Primary micro limit | Electrode wear and measurement resolution |
| Main limitation | Loose-tolerance or easily accessible features are rarely economical with Micro EDM. |
Quality Target Reference
| Requirement | Planning range | What it means in practice |
|---|---|---|
| High-precision tolerance | ±0.005–0.010 mm | Plan finishing passes, thermal stability and inspection from the same datum scheme. |
| Fine finish | Ra 0.8–1.6 μm | Usually needs a finishing pass or lower-energy discharge on the specified surface. |
Material Condition Reference
| Condition | What to expect | Watch out for | Surface notes |
|---|---|---|---|
| as-sintered or supplied condition | Use low-force fixturing and conservative discharge energy. | Brittle edges can chip or binder-rich zones can erode unevenly. | Inspect edge breakout and surface integrity rather than Ra alone. |
| stress-relieved or recrystallized | Use stable support and reduced energy on finished stock. | Grinding stress or porosity can cause local cracking. | Apply selective polishing or lapping where practical. |
Tolerance & Surface Requirements
For Micro EDM at ±0.005–0.010 mm and Ra 0.8–1.6 μm, apply the finish only to the faces named on the drawing. On Pure Tungsten, use conservative energy, strong support and inspection focused on edge chipping and subsurface damage. Roughness does not replace recast, edge, corrosion, crack, or post-process acceptance where those items affect function.
Pure Tungsten Micro EDM Quality Checkpoints
- Mark the dimensions that actually need ±0.005–0.010 mm and use the same datum for machining and inspection.
- Circle the faces that need Ra 0.8–1.6 μm; leave nonfunctional surfaces at a practical production finish.
- State the Pure Tungsten condition, Micro EDM finishing strategy, measurement method, and any recast or edge requirement.
Limits and Better Alternatives
Main Limit
±0.005–0.010 mm and Ra 0.8–1.6 μm are selected-feature planning references for Pure Tungsten in Micro EDM, not unconditional whole-part guarantees.
Consider Another Route When
Use conventional EDM for larger features, precision laser processing for suitable thin geometry, or mechanical micro-drilling where a tool can reach.
Practical Next Step
Send the Pure Tungsten drawing with the Micro EDM features that need ±0.005–0.010 mm, the faces that need Ra 0.8–1.6 μm, the supplied condition, quantity, datums, and inspection method.
Practical Takeaway
On Pure Tungsten, plan ±0.005–0.010 mm and Ra 0.8–1.6 μm together for the selected Micro EDM features. Use one datum and one inspection plan, and apply the tightest values only where they control function.
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: Micro EDM
- Material: Pure Tungsten
- 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.