Looking for reliable CNC Sinker EDM Stainless Steel? VT machining manufactures Stainless Steel parts to tight tolerances and consistent quality. Stainless Steel is corrosion resistant, strong, hygienic (304/316 grades), so the process is set up specifically for the material.
Process Data for CNC Sinker EDM Stainless Steel
| 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 304 Stainless Steel, the most common Stainless Steel grade we see for CNC Sinker EDM. Typical values for 304 Stainless Steel, Annealed; confirmed on the first part.
CNC Sinker EDM Capability for Stainless Steel
- Blind cavities & ribs
- Fine surface (VDI grades)
- Tolerance to ±0.005 mm
- Hardened tool steel
Stainless Steel material properties, finishing options and grade notes are on our CNC Wire EDM Stainless Steel page.
How CNC Sinker EDM Stainless Steel Works
Material is removed from the Stainless Steel 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 Stainless Steel
| 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 Stainless Steel 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 Stainless Steel
A few design choices make a real difference to cost and quality. EDM suits sharp internal corners, thin ribs and hardened Stainless Steel 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 Stainless Steel
CNC Sinker EDM of Stainless Steel 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.
Typical Stainless Steel Parts for CNC Sinker EDM
Illustrative examples of CNC Sinker EDM Stainless Steel 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.
Extrusion die
- Material
- Stainless Steel
- 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
- Stainless Steel
- 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
- Stainless Steel
- 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.
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 Stainless Steel
- 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 Stainless Steel 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 Stainless Steel
Send the drawing, the Stainless Steel grade and the quantity. You get pricing, lead time and any DFM notes back — usually within one business day.
Request a QuoteFrequently Asked Questions
Which industries use CNC Sinker EDM Stainless Steel parts?
CNC Sinker EDM Stainless Steel parts are used across aerospace, medical, automotive, electronics, semiconductor and general industrial sectors — anywhere precise Stainless Steel components are required.
Why is Stainless Steel a good choice for CNC Sinker EDM?
Stainless Steel is corrosion resistant, strong, hygienic (304/316 grades), which makes it well suited to CNC Sinker EDM. We tune the process to the alloy so the finished Stainless Steel EDM machining part meets your dimensional and functional requirements.
What material thickness or size range suits CNC Sinker EDM Stainless Steel?
We machine Stainless Steel across a broad size range; share your part envelope for confirmation.
Does CNC Sinker EDM Stainless Steel require dedicated tooling?
Wire EDM needs no shaped tooling; sinker EDM uses a shaped electrode we produce in-house for your cavity.
What surface finish is achievable on Stainless Steel with CNC Sinker EDM?
Surface finish on Stainless Steel is controlled to your specification; we confirm the achievable Ra against your callout.
Can you EDM-machine hardened Stainless Steel?
Yes. EDM removes material by electrical discharge rather than cutting force, so hardened and difficult Stainless Steel can be machined to fine detail and tight tolerance without distortion.