VT machining provides CNC Milling Bronze for customers who need accurate, repeatable Bronze components. Because Bronze is wear resistant with good bearing properties, we adapt the process to suit — controlling the variables that matter for this alloy.
CNC Milling Capability for Bronze
- 3-, 4- and 5-axis capability
- Tolerance to ±0.01 mm
- Pocket/slot/contour features
- Spindle speeds to 12,000+ rpm
Bronze Material Data
| Density | 8.80 g/cm³ |
|---|---|
| Tensile strength | 240 MPa |
| Yield strength (0.2%) | 125 MPa |
| Hardness | 65 HB |
| Melting point | 855–980 °C |
| Thermal conductivity | 59 W/m·K |
| Thermal expansion | 18.0 ×10⁻⁶/K |
| Electrical conductivity | 12% |
| Machinability (C36000 = 100%) | 70% |
| Grades we run | C93200 SAE 660, C54400, C63000 aluminium bronze, C86300 manganese bronze |
Published typical values for C93200 (SAE 660). Other grades in the family differ — the certificate supplied with your order carries the actual heat-lot figures.
Cast bearing bronze has porosity. On sealing faces we specify continuous-cast stock rather than sand-cast, because a pinhole in a bore face is not repairable.
How CNC Milling Bronze Works
Rotating multi-flute cutters remove material as the Bronze workpiece is driven through programmed tool paths on 3-, 4- or 5-axis machining centres. Climb milling, step-over and depth-of-cut are set so chip load stays in the ideal band for the alloy.
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 Milling Bronze
| Feature | Standard | Precision |
|---|---|---|
| Linear dimension (< 100 mm) | ±0.05 mm | ±0.010 mm |
| Linear dimension (100–300 mm) | ±0.10 mm | ±0.025 mm |
| Hole diameter (reamed) | H9 | H7 |
| True position of hole pattern | ±0.10 mm | ±0.025 mm |
| Flatness over 100 mm | 0.05 mm | 0.015 mm |
| Perpendicularity | 0.10 mm | 0.020 mm |
| Surface finish, as machined | Ra 1.6 µm | Ra 0.4 µm |
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 Bronze
Bronze is wear resistant with good bearing properties. 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.
CNC Milling Quality & Inspection
Quality is built in, not inspected on. We monitor key features during the run and confirm them at final inspection, with CMM verification available for tight tolerances. We provide the inspection and traceability records your quality system requires.
Secondary Operations & Finishing
Most Bronze parts need some finishing, which we manage in-house or through vetted partners. Options include deburring and edge-breaking, heat treatment, surface grinding, polishing, and plating or anodising for corrosion resistance and appearance. Give us the finished-part requirement and we will sequence every operation correctly.
CNC Milling Tolerances & Surface Finish
For CNC Milling, dimensional and positional tolerances around ±0.01 mm are routine, tightening toward ±0.005 mm on precision setups. Surface finish on machined faces typically falls in the Ra 0.4–1.6 µm range depending on tooling and pass strategy.
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 Milling Bronze
Small design adjustments often cut cost and lead time. Generous internal radii, sensible pocket depth-to-width ratios and avoiding very thin unsupported walls all reduce cost and improve accuracy in Bronze. If you send your model early, we will return practical DFM feedback before you commit to production.
Applications of CNC Milling Bronze
Bronze parts made this way are found throughout aerospace, medical, automotive, electronics and industrial equipment. Prototype, bridge and production volumes are all welcome.
How to Order CNC Milling Bronze
Starting your project takes one email. Send your CAD or 2D drawing, the Bronze grade and condition, the quantity and any finish or inspection requirements. We respond quickly with price, lead time and any DFM notes, in clear English.
Parts We Have Run in Bronze
Three representative CNC Milling Bronze 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.
Vacuum chamber flange
- Material
- Bronze
- Size
- Ø180 × 20 mm
- Key callouts
- Knife-edge seal Ra 0.4 µm, bolt circle ±0.05 mm
- Batch
- 60 pcs
Sealing face finished last, then handled in gloves and bagged straight off the machine.
Optical mount plate
- Material
- Bronze
- Size
- 160 × 160 × 12 mm
- Key callouts
- Hole pattern true position ±0.02 mm, flatness 0.01 mm
- Batch
- 40 pcs
Roughed, stress-relieved overnight, then finished — the plate is too thin to hold flatness in one hit.
Sensor housing
- Material
- Bronze
- Size
- 86 × 54 × 22 mm
- Key callouts
- Pocket depth ±0.02 mm, bore H7, flatness 0.015 mm
- Batch
- 250 pcs / quarter
O-ring groove finished in the same setup as the sealing face so the two stay parallel.
Finishing Options for Bronze
| 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 Milling Bronze
- 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 Bronze 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 Milling
Other Processes for Bronze
Send the drawing, the Bronze 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 is CNC Milling Bronze and how is it done?
CNC Milling Bronze refers to multi-axis milling cutters remove material to produce prismatic features, pockets, slots and contoured 3D surfaces. Applied to Bronze — wear resistant with good bearing properties — VT machining produces each part to your CAD drawing, selecting parameters from your tolerance, finish and quantity requirements.
What material thickness or size range suits CNC Milling Bronze?
We machine Bronze across a broad size range; share your part envelope for confirmation.
Can VT machining make custom Bronze parts to my drawing?
Yes. Bronze Bronze 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 surface finish is achievable on Bronze with CNC Milling?
Surface finish on Bronze is controlled to your specification; we confirm the achievable Ra against your callout.