CNC Sinker EDM Tungsten is a core capability at VT machining. We combine controlled EDM machining with material-aware setup for Tungsten — an alloy that is extreme hardness, density and heat resistance — to produce parts that meet your specification first time.
CNC Sinker EDM Capability for Tungsten
- Blind cavities & ribs
- Fine surface (VDI grades)
- Tolerance to ±0.005 mm
- Hardened tool steel
Tungsten Material Data
| Density | 19.25 g/cm³ |
|---|---|
| Tensile strength | 750–1500 MPa |
| Yield strength (0.2%) | 550 MPa |
| Hardness | 350–500 HV |
| Melting point | 3422 °C |
| Thermal conductivity | 173 W/m·K |
| Thermal expansion | 4.5 ×10⁻⁶/K |
| Electrical conductivity | 31% |
| Machinability (C36000 = 100%) | grind / EDM only |
| Grades we run | Pure W (99.95%), W-Ni-Fe heavy alloy (17.0–18.5 g/cm³), WC-Co |
Published typical values for Pure W / W-Ni-Fe. Other grades in the family differ — the certificate supplied with your order carries the actual heat-lot figures.
Conventional cutting is not on the table for pure tungsten. Features are wire-EDM cut and ground; expect longer lead time than any other metal on the list.
How CNC Sinker EDM Tungsten Works
Material is removed from the Tungsten workpiece by controlled electrical discharges across a dielectric gap, with no mechanical contact. Flushing, on/off pulse timing and electrode/wire feed are set to balance speed against surface finish.
Every job begins from your CAD model or 2D drawing. Fixturing and tool paths are planned so the most critical dimensions are produced in the most rigid, repeatable setup. Critical dimensions are checked on the first part and monitored through the run.
Achievable Tolerances for CNC Sinker EDM Tungsten
| Feature | Standard | Precision |
|---|---|---|
| Profile dimension | ±0.010 mm | ±0.002 mm |
| Internal corner radius | 0.15 mm | 0.05 mm |
| Taper control over 50 mm | 0.02 mm | 0.005 mm |
| Surface finish (skim passes) | Ra 0.8 µm | Ra 0.2 µm |
| Recast layer | 10 µm | 2 µm (fine skim) |
| Start-hole diameter | 1.0 mm | 0.25 mm |
| Workpiece hardness | no limit (conductive) | no limit (conductive) |
Standard is what a normal quotation assumes. Precision is available on nominated features and is priced separately, because it needs extra setups, in-process gauging and CMM verification. Call out only the features that need it — blanket-tightening a drawing is the single most common reason a quote comes back expensive.
Secondary Operations & Finishing
We complete Tungsten components with the secondary steps your drawing calls for. We arrange heat treatment, surface treatment, marking and assembly as needed. Tell us the final spec and we will plan the full route so parts arrive ready to use.
CNC Sinker EDM Tolerances & Surface Finish
EDM holds tolerances to roughly ±0.002–0.005 mm with no cutting force on the Tungsten part, producing fine, controlled surface textures and sharp internal corners impossible to mill.
Final tolerances are governed by the material's behaviour, wall thickness and overall stiffness. We give honest DFM feedback if a callout would be costly or better achieved another way.
Design Tips for CNC Sinker EDM Tungsten
A few design choices make a real difference to cost and quality. EDM suits sharp internal corners, thin ribs and hardened Tungsten that cannot be milled; allowing a small corner radius where possible speeds the cut. If you send your model early, we will return practical DFM feedback before you commit to production.
CNC Sinker EDM Quality & Inspection
Consistent quality comes from disciplined process control. Critical dimensions on Tungsten parts are checked in-process and verified at final inspection using calibrated instruments and, where required, CMM measurement. Full documentation — dimensional reports, mill certs, FAIR — is available when your programme needs it.
Working with Tungsten
Tungsten offers a useful combination of properties: it is extreme hardness, density and heat resistance. Those characteristics shape how we approach EDM — from tool and parameter selection to work-holding and coolant.
If your application is sensitive to alloy condition, we agree the specification in writing and document it. Stock is sourced from reputable suppliers so what you order is what you receive.
Applications of CNC Sinker EDM Tungsten
CNC Sinker EDM of Tungsten supports parts across aerospace, medical, automotive, electronics, semiconductor, energy and general industrial sectors. We scale from one-off prototypes to ongoing production while holding the same quality.
How to Order CNC Sinker EDM Tungsten
Ordering Tungsten parts is straightforward. Provide the drawing, material, quantity and any certification needs. Our engineers reply — in English — with feasibility, pricing and a realistic lead time, usually within one business day.
Parts We Have Run in Tungsten
Three representative CNC Sinker EDM Tungsten jobs, with the callouts that actually drove the process plan. Yours will differ — these are here so you can judge whether your part is in our range before you spend time on an RFQ.
Extrusion die
- Material
- Tungsten
- Size
- 120 × 120 × 25 mm
- Key callouts
- Profile ±0.005 mm, internal corner R0.1 mm
- Batch
- 35 pcs
Cut in four skim passes; the first pass is speed, the last three are finish and accuracy.
Turbine blade fir-tree root
- Material
- Tungsten
- Size
- 40 × 25 mm section
- Key callouts
- Profile ±0.008 mm
- Batch
- 120 pcs
Held on a dedicated fixture so every blade in the set indexes identically.
Injection mould cavity rib
- Material
- Tungsten
- Size
- 0.25 mm wide × 8 mm deep
- Key callouts
- Width ±0.005 mm, VDI 21 finish
- Batch
- 45 pcs
Sinker EDM with a graphite electrode; a cutter that thin would break in the first pass.
Finishing Options for Tungsten
| Finish | Thickness / effect | Why it gets specified |
|---|---|---|
| Deburr / edge break | 0.05–0.3 mm | All parts unless the drawing says otherwise |
| Bead blast | Ra 1.6–3.2 µm | Uniform matt finish, hides tool marks |
| Laser marking | — | Part number, lot code, data matrix |
No drawing yet? Build one in the browser.
Set the metal, dimensions and features, watch the 3D model update as you type, then switch to the 2D sheet to add dimensions and tolerances. Download it or send it straight to us with your RFQ.
What We Need to Quote CNC Sinker EDM Tungsten
- GeometrySTEP or IGES for the 3D model, plus a PDF drawing if you have tolerance callouts. A dimensioned sketch is enough to start.
- MaterialThe exact Tungsten grade and condition — temper, heat-treat state or hardness. If you are not sure, tell us the function and we will suggest one.
- QuantityPrototype count and the expected annual volume. Both change how the part is made and therefore what it costs.
- TolerancesWhich features are critical. Everything else runs to our standard tolerance, which is what keeps the price sensible.
- FinishSurface treatment, cosmetic requirements, and any faces that must be masked.
- DocumentsWhether you need a material certificate, dimensional report, FAIR or PPAP with the shipment.
Missing something from the list is not a problem — send what you have. We will come back with the specific questions rather than a generic form.
Other Metals for CNC Sinker EDM
Other Processes for Tungsten
Send the drawing, the Tungsten grade and the quantity. You get pricing, lead time and any DFM notes back — usually within one business day.
Request a QuoteFrequently Asked Questions
Why is Tungsten a good choice for CNC Sinker EDM?
Tungsten is extreme hardness, density and heat resistance, which makes it well suited to CNC Sinker EDM. We tune the process to the alloy so the finished Tungsten EDM machining part meets your dimensional and functional requirements.
What is CNC Sinker EDM Tungsten and how is it done?
CNC Sinker EDM Tungsten refers to sinker (die-sink) EDM burns a shaped electrode into metal to form precise cavities and blind features. Applied to Tungsten — extreme hardness, density and heat resistance — VT machining produces each part to your CAD drawing, selecting parameters from your tolerance, finish and quantity requirements.
Does CNC Sinker EDM Tungsten require dedicated tooling?
Wire EDM needs no shaped tooling; sinker EDM uses a shaped electrode we produce in-house for your cavity.
Which industries use CNC Sinker EDM Tungsten parts?
CNC Sinker EDM Tungsten parts are used across aerospace, medical, automotive, electronics, semiconductor and general industrial sectors — anywhere precise Tungsten components are required.
Can VT machining make custom Tungsten parts to my drawing?
Yes. Tungsten Tungsten EDM machining is made to order from your CAD/2D drawing. Share your geometry, material grade, tolerance and quantity and we will confirm feasibility, lead time and pricing.
What tolerances can you hold for CNC Sinker EDM Tungsten?
Achievable tolerances for Tungsten EDM machining depend on the alloy, geometry and feature size. EDM holds tolerances to around ±0.002 mm with no cutting force on the part. Exact figures are confirmed against your drawing callouts.