Precision Sinker EDM Machining
Machining the impossible. We sink custom-shaped graphite and copper electrodes into hardened tool steels, Tungsten Carbide, and Inconel to create complex blind cavities with ±0.005mm accuracy.
When traditional CNC endmills fail against HRC 60+ hardened metals, or when your design requires razor-sharp internal corners and deep, narrow ribs, Die Sinker EDM is the ultimate solution. By discharging controlled electrical sparks submerged in dielectric fluid, we erode the toughest conductive materials with zero mechanical contact—meaning zero tool pressure, no part distortion, and flawless surface finishes down to Ra 0.2 µm.
Japanese Market
Machining Precision
DFM Feedback
CNC Centers
IP Protection
Which Precision Process Do You Need?
Not sure if your part requires CNC Milling, Wire EDM, or Sinker EDM? Use our engineering matrix to determine the most cost-effective and accurate process for your geometry.
| Process Feature | Sinker EDM (Die Sinking) | Wire EDM | 5-Axis CNC Milling |
|---|---|---|---|
| Core Mechanism | A 3D shaped Sinker EDM electrode "sinks" into the part, creating a negative cavity. | A thin continuous wire acts like a highly precise digital bandsaw. | A spinning rotary cutter (endmill) physically shears material away. |
| Best Suited For | Blind cavities, internal hexes, deep narrow ribs, injection molds. | Through-holes, complex extrusions, thick metal plates. | Rapid material removal, large 3D organic shapes, plastics. |
| Material Hardness | No Limit (Cuts Tungsten Carbide) | No Limit (Conductive only) | Limited (Usually struggles above HRC 60). |
| Mechanical Stress | Zero (No tool contact = No distortion) | Zero (No contact) | High cutting forces (can warp thin walls). |
Die Sinking Cost Estimator
Sinker EDM pricing relies on two factors: CNC milling the custom electrode, and the spark erosion cycle time. Input your cavity complexity and material hardness below for an instant baseline projection.
The Science of the Electrode
In Sinker EDM, the precision of the final part is dictated entirely by the precision of the electrode. At 3Q Machining, we manufacture our own electrodes in-house using dedicated high-speed mills, ensuring total quality control.
Graphite Electrodes
The most preferred choice for large mold cavities. Graphite offers incredible heat and wear resistance, allowing for aggressive Material Removal Rates (MRR) without electrode deformation.
Copper & Copper-Tungsten
Used for ultra-fine details, micro-holes, and achieving the absolute smoothest surface finishes (VDI 0 / Ra 0.1 µm). Copper-Tungsten is exceptionally resistant to spark erosion wear, ideal for sharp internal corners.
Technical Specifications
- Max Dimensional Tolerance: ±0.005 mm (±0.0002")
- Internal Corner Radii: As small as R 0.02 mm
- Surface Finish: Ra 0.2 µm to Ra 3.2 µm (Controllable via spark frequency)
- Dielectric Medium: High-grade hydrocarbon oil (prevents oxidation on sensitive steel parts during machining).
Sinker EDM FAQ
How much does Sinker EDM cost?
Can Sinker EDM machine plastics or ceramics?
Why not just use Wire EDM?
Why is "Flushing" so critical in Sinker EDM?
How do you compensate for Electrode Wear?
What type of Dielectric Fluid do you use?
Have an "Impossible" Part?
Upload your CAD model today. If it has sharp internal corners, blind splines, or requires hardened steel, our EDM experts will quote it instantly.
Request EDM Quote
