VT machining provides CNC Polishing 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 Polishing Capability for Bronze
- Mirror finish capable
- Ra to 0.05 µm
- Cosmetic & sealing faces
- Multi-stage abrasives
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 Polishing Bronze Works
Abrasive media or tooling refine the Bronze surface in controlled stages, removing the previous step's marks until the target roughness and edge condition are reached.
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 Polishing Bronze
| Feature | Standard | Precision |
|---|---|---|
| Surface roughness | Ra 0.8 µm | Ra 0.05 µm |
| Edge break | 0.1–0.3 mm | 0.05 ±0.02 mm |
| Material removed | 0.02 mm | 0.005 mm |
| Bore roundness after honing | 0.005 mm | 0.002 mm |
| Cross-hatch angle | 45° ±10° | 45° ±5° |
| Cosmetic grade | uniform satin | mirror, no visible lines |
| Masking of datum faces | on request | standard |
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 Polishing Tolerances & Surface Finish
Finishing brings Bronze to a defined roughness target — from a uniform satin to Ra values as low as 0.05 µm — with controlled, repeatable edge breaks.
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.
CNC Polishing 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.
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.
Design Tips for CNC Polishing Bronze
Small design adjustments often cut cost and lead time. Telling us the target Ra, the cosmetic faces and any masking needs lets us finish Bronze efficiently without over-processing. If you send your model early, we will return practical DFM feedback before you commit to production.
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.
Applications of CNC Polishing 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 Polishing 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 Polishing 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.
Deburred stamping
- Material
- Bronze
- Size
- 40 × 25 × 1 mm
- Key callouts
- Edge break 0.05–0.15 mm, no sharp edges
- Batch
- 30,000 pcs
Vibratory finished in media sized to reach every internal cutout.
Cosmetic housing
- Material
- Bronze
- Size
- 150 × 90 mm visible face
- Key callouts
- Uniform satin, no directional lines
- Batch
- 2,500 pcs
Grained in one direction with datum faces masked so they keep their tolerance.
Sealing face
- Material
- Bronze
- Size
- Ø60 mm face
- Key callouts
- Ra 0.2 µm, flatness 0.005 mm
- Batch
- 1,000 pcs
Lapped after grinding; the seal spec is a roughness number, not a dimension.
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 Polishing 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 Polishing
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 Polishing Bronze and how is it done?
CNC Polishing Bronze refers to cNC polishing refines surfaces to a smooth, reflective finish for cosmetic and functional needs. 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.
Why is Bronze a good choice for CNC Polishing?
Bronze is wear resistant with good bearing properties, which makes it well suited to CNC Polishing. We tune the process to the alloy so the finished Bronze finishing part meets your dimensional and functional requirements.
What tolerances can you hold for CNC Polishing Bronze?
Achievable tolerances for Bronze finishing depend on the alloy, geometry and feature size. We hold tight, repeatable tolerances appropriate to the feature and material. Exact figures are confirmed against your drawing callouts.
What is the typical lead time and minimum order for CNC Polishing Bronze?
CNC Polishing prototypes for Bronze can be produced quickly and scaled to series production. Send your drawing and quantity and we will advise lead time and any minimum order.