CNC Sinker EDM Inconel is a core capability at VT machining. We combine controlled EDM machining with material-aware setup for Inconel — an alloy that is high-temperature strength and oxidation resistance — to produce parts that meet your specification first time.
Process Data for CNC Sinker EDM Inconel
| Electrode | Graphite (roughing) / copper (fine finish) |
|---|---|
| Relative removal rate | Medium (vs tool steel = medium) |
| Best finish | VDI 12-18 (Ra 0.4-0.8 µm) |
Shown for Inconel 718, the most common Inconel grade we see for CNC Sinker EDM. Typical values for Inconel 718, Solution-treated or aged; confirmed on the first part.
CNC Sinker EDM Capability for Inconel
- Blind cavities & ribs
- Fine surface (VDI grades)
- Tolerance to ±0.005 mm
- Hardened tool steel
Inconel material properties, finishing options and grade notes are on our CNC Wire EDM Inconel page.
How CNC Sinker EDM Inconel Works
Material is removed from the Inconel 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.
We start from your supplied geometry and tolerance scheme. The setup is designed to minimise re-clamping, which protects positional accuracy across features. A first article is verified against the drawing before the balance of the batch is released.
Achievable Tolerances for CNC Sinker EDM Inconel
| 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.
CNC Sinker EDM Tolerances & Surface Finish
EDM holds tolerances to roughly ±0.002–0.005 mm with no cutting force on the Inconel part, producing fine, controlled surface textures and sharp internal corners impossible to mill.
The tightest tolerances are reserved for the features your drawing flags as critical. Share your tolerance scheme and we will confirm what is realistic before quoting.
Design Tips for CNC Sinker EDM Inconel
Small design adjustments often cut cost and lead time. EDM suits sharp internal corners, thin ribs and hardened Inconel 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.
Applications of CNC Sinker EDM Inconel
Inconel parts made this way are found throughout aerospace, medical, automotive, electronics and industrial equipment. Prototype, bridge and production volumes are all welcome.
Typical Inconel Parts for CNC Sinker EDM
Illustrative examples of CNC Sinker EDM Inconel parts and the callouts that usually drive the process plan. They show the kind of work that fits this process; they are not specific customer orders.
Carbide punch
- Material
- Inconel
- Size
- Ø6 × 45 mm
- Key callouts
- OD ±0.003 mm, sharp form retained
- Batch
- 250 pcs
Carbide is EDM or grind only; there is no milling route.
Micro slot in nozzle
- Material
- Inconel
- Size
- 0.15 mm wide × 6 mm deep
- Key callouts
- Width ±0.003 mm
- Batch
- 400 pcs
Cut with 0.1 mm wire; the start hole is EDM-drilled at Ø0.3 mm.
Turbine blade fir-tree root
- Material
- Inconel
- 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.
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 Inconel
- 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 Inconel 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 Inconel
Send the drawing, the Inconel grade and the quantity. You get pricing, lead time and any DFM notes back — usually within one business day.
Request a QuoteFrequently Asked Questions
What surface finish is achievable on Inconel with CNC Sinker EDM?
Surface finish on Inconel is controlled to your specification; we confirm the achievable Ra against your callout.
What material thickness or size range suits CNC Sinker EDM Inconel?
We machine Inconel across a broad size range; share your part envelope for confirmation.
Can you EDM-machine hardened Inconel?
Yes. EDM removes material by electrical discharge rather than cutting force, so hardened and difficult Inconel can be machined to fine detail and tight tolerance without distortion.
Which industries use CNC Sinker EDM Inconel parts?
CNC Sinker EDM Inconel parts are used across aerospace, medical, automotive, electronics, semiconductor and general industrial sectors — anywhere precise Inconel components are required.