VT machining provides CNC Wire EDM Brass for customers who need accurate, repeatable Brass components. Because Brass is free-machining, good conductivity, attractive finish, we adapt the process to suit — controlling the variables that matter for this alloy.
Process Data for CNC Wire EDM Brass
| Area cutting rate (0.25 mm brass wire) | ~140 mm²/min |
|---|---|
| Linear speed at 10 mm thick | ~14 mm/min |
| Linear speed at 30 mm thick | ~4.7 mm/min |
| Linear speed at 60 mm thick | ~2.3 mm/min |
| Achievable accuracy | ±0.005 mm with 3-4 skim passes; Ra 0.4-0.8 µm |
Shown for C360 Brass, the most common Brass grade we see for CNC Wire EDM. Typical values for C360 Brass, Half-hard; confirmed on the first part.

CNC Wire EDM Capability for Brass
- Kerf from 0.1 mm
- Tolerance to ±0.002 mm
- Hardened & exotic alloys
- Sharp internal corners
Brass Material Data
| Density | 8.50 g/cm³ |
|---|---|
| Tensile strength | 340–470 MPa |
| Yield strength (0.2%) | 125–310 MPa |
| Hardness | 78–130 HB |
| Melting point | 885–900 °C |
| Thermal conductivity | 115 W/m·K |
| Thermal expansion | 20.5 ×10⁻⁶/K |
| Electrical conductivity | 26% |
| Machinability (C36000 = 100%) | 100% (the benchmark) |
| Grades we run | C36000 free-cutting, C37700 forging, C26000 cartridge, C46400 naval |
Published typical values for C36000. Other grades in the family differ — the certificate supplied with your order carries the actual heat-lot figures.
Nothing much — this is the easiest metal in the shop. Worth asking about if a copper or bronze part is cost-driven rather than conductivity-driven.
How CNC Wire EDM Brass Works
Material is removed from the Brass 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 Wire EDM Brass
| 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.
Working with Brass
Brass is free-machining, good conductivity, attractive finish. We translate those properties into a process plan: the right tooling, speeds, feeds and fixturing for the alloy.
Where the grade, temper or heat-treat condition matters to performance, we confirm it with you and can supply material certificates. Material is procured to recognised standards for consistent, repeatable results.
Design Tips for CNC Wire EDM Brass
Small design adjustments often cut cost and lead time. EDM suits sharp internal corners, thin ribs and hardened Brass 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 Wire EDM Tolerances & Surface Finish
EDM holds tolerances to roughly ±0.002–0.005 mm with no cutting force on the Brass 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.
Applications of CNC Wire EDM Brass
Brass parts made this way are found throughout aerospace, medical, automotive, electronics and industrial equipment. Prototype, bridge and production volumes are all welcome.
Typical Brass Parts for CNC Wire EDM
Illustrative examples of CNC Wire EDM Brass 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
- Brass
- 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
- Brass
- 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
- Brass
- 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 Brass
| Finish | Thickness / effect | Why it gets specified |
|---|---|---|
| Nickel plate | 5–15 µm | Hard, bright, corrosion resistant |
| Chrome plate | 0.3–1 µm | Decorative, over nickel |
| Clear lacquer | 10–20 µm | Stops the natural tarnish |
| Tin plate | 3–15 µm | Solderable contacts |
| 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 Wire EDM Brass
- 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 Brass 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 Wire EDM
Other Processes for Brass
Send the drawing, the Brass 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 Brass a good choice for CNC Wire EDM?
Brass is free-machining, good conductivity, attractive finish, which makes it well suited to CNC Wire EDM. We tune the process to the alloy so the finished Brass EDM machining part meets your dimensional and functional requirements.
Does CNC Wire EDM Brass require dedicated tooling?
Wire EDM needs no shaped tooling; sinker EDM uses a shaped electrode we produce in-house for your cavity.
How clean are the edges produced by CNC Wire EDM on Brass?
Machined Brass edges are clean and to specification; edge-break or deburring is added when your drawing calls for it.
What tolerances can you hold for CNC Wire EDM Brass?
Achievable tolerances for Brass 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.
