VT machining provides CNC Centerless Grinding 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 Centerless Grinding Capability for Bronze
- No center holes needed
- High throughput
- Diameter ±0.003 mm
- Through-feed & in-feed
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 Centerless Grinding Bronze Works
An abrasive wheel removes a fine, controlled layer from the Bronze part. Wheel specification, dressing interval, infeed and coolant are matched to the alloy's hardness so the surface is not burned or left with residual stress.
Programming is driven directly by your 3D model or print. Work-holding, tool selection and the cutting strategy are planned around the critical features and the material before the first chip is cut. First-off inspection confirms the process is centred before production continues.
Achievable Tolerances for CNC Centerless Grinding Bronze
| Feature | Standard | Precision |
|---|---|---|
| Size (OD, ID, thickness) | ±0.005 mm | ±0.002 mm |
| Flatness over 100 mm | 0.010 mm | 0.003 mm |
| Parallelism | 0.010 mm | 0.003 mm |
| Roundness | 0.005 mm | 0.002 mm |
| Squareness | 0.010 mm | 0.005 mm |
| Surface finish | Ra 0.4 µm | Ra 0.1 µm |
| Workpiece hardness | up to 62 HRC | up to 65 HRC |
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 Centerless Grinding Quality & Inspection
We control quality throughout the process, not just at the end. In-process checks plus final inspection — including CMM where specified — keep every Bronze part to print. Inspection reports, material certificates and first-article documentation can be supplied on request.
Design Tips for CNC Centerless Grinding Bronze
We are happy to suggest design tweaks that improve manufacturability. Allowing adequate grind stock, specifying realistic flatness over the true datum, and relieving corners help us hit tight tolerances on Bronze efficiently. If you send your model early, we will return practical DFM feedback before you commit to production.
Working with Bronze
As a material, Bronze is wear resistant with good bearing properties. Our setup reflects the alloy's machinability so the finished part is accurate and free of avoidable defects.
We verify the exact grade and condition before machining, and traceable mill certs are available on request. We can work to your nominated material source or specification when required.
Secondary Operations & Finishing
Finished Bronze parts can move straight into secondary operations under one roof. Typical add-ons are deburring, passivation, anodising, plating, blasting, polishing and laser marking. We coordinate the whole chain so you receive complete, inspection-ready parts.
CNC Centerless Grinding Tolerances & Surface Finish
Ground Bronze reaches single-micron tolerances on size, flatness and parallelism, with surface finishes down to Ra 0.1–0.4 µm — and a near-mirror finish on suitable alloys.
Exact achievable figures depend on the alloy, the feature size and the part geometry. Tell us which dimensions are critical and we will advise feasibility up front.
Applications of CNC Centerless Grinding Bronze
Customers order CNC Centerless Grinding Bronze components for everything from instrumentation to structural and functional assemblies. Whether you need a single prototype or recurring production volume, the same process discipline applies.
How to Order CNC Centerless Grinding Bronze
Getting a quote is simple. Share your model, the material grade, your quantity and target tolerances. You receive a clear quotation with lead time and honest manufacturability feedback.
Parts We Have Run in Bronze
Three representative CNC Centerless Grinding 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.
Mould insert
- Material
- Bronze
- Size
- 80 × 60 × 25 mm
- Key callouts
- Flatness 0.003 mm, squareness 0.005 mm
- Batch
- 90 pcs
Surface ground on all six faces so the insert seats without shimming.
Ceramic-coated shaft journal
- Material
- Bronze
- Size
- Ø45 × 180 mm
- Key callouts
- OD ±0.003 mm, roundness 0.002 mm, Ra 0.2 µm
- Batch
- 150 pcs
Ground after coating; the coating is never the final dimension.
Punch tool
- Material
- Bronze
- Size
- Ø10 × 60 mm
- Key callouts
- OD ±0.002 mm, roundness 0.002 mm, Ra 0.1 µm
- Batch
- 300 pcs
Cylindrical ground after hardening to 60 HRC — machining soft would not hold the size.
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 Centerless Grinding 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 Centerless Grinding
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 Centerless Grinding Bronze and how is it done?
CNC Centerless Grinding Bronze refers to centerless grinding supports the workpiece on a blade between wheels for high-throughput OD finishing. 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.
Does CNC Centerless Grinding Bronze require dedicated tooling?
Most Bronze grinding work uses standard cutting tools and CNC programs; dedicated fixtures are made only when geometry or volume requires them.
What tolerances can you hold for CNC Centerless Grinding Bronze?
Achievable tolerances for Bronze grinding depend on the alloy, geometry and feature size. Grinding routinely holds single-micron tolerances on diameter, flatness and parallelism. Exact figures are confirmed against your drawing callouts.
What surface finish is achievable on Bronze with CNC Centerless Grinding?
Grinding can take Bronze to a fine finish — typically Ra 0.1–0.4 µm, and to a mirror grade on suitable alloys.
How clean are the edges produced by CNC Centerless Grinding on Bronze?
Machined Bronze edges are clean and to specification; edge-break or deburring is added when your drawing calls for it.
