VT machining provides CNC Punching 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.
Process Data for CNC Punching Bronze
| Die clearance per side | 8% of thickness (0.16 mm at 2 mm) |
|---|---|
| Punch force, Ø10 hole in 2 mm | ~29.4 kN (3 t) |
| Minimum hole diameter | ≥ 1 × thickness |
Shown for C954 Aluminum Bronze, the most common Bronze grade we see for CNC Punching. Typical values for C954 Aluminum Bronze, As cast or heat-treated; confirmed on the first part.
CNC Punching Capability for Bronze
- Sheet thickness 0.5–6 mm
- Hole position repeatability ±0.10 mm
- Punch/die clearance set per material
- Louver, emboss and tap-extrude tooling
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 Punching Bronze Works
A CNC turret presses hardened punches through the Bronze sheet into matching dies. Punch-to-die clearance is set as a percentage of thickness so the cut edge stays clean and burr is minimal.
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 Punching Bronze
| Feature | Standard | Precision |
|---|---|---|
| Hole position across sheet | ±0.15 mm | ±0.10 mm |
| Hole diameter | ±0.10 mm | ±0.05 mm |
| Overall blank size | ±0.20 mm | ±0.10 mm |
| Minimum hole | 1.0 × thickness | 0.8 × thickness |
| Hole-to-edge distance | 2.0 × thickness | 1.5 × thickness |
| Burr height | 0.08 mm | 0.03 mm (deburred) |
| Sheet thickness range | 0.5–6.0 mm | 0.5–3.0 mm |
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.
Design Tips for CNC Punching Bronze
We are happy to suggest design tweaks that improve manufacturability. Keeping hole-to-edge and hole-to-hole distances at least 1.5–2× thickness avoids distortion and tearing in punched Bronze. 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.
CNC Punching Tolerances & Surface Finish
Punched Bronze holds hole-position repeatability around ±0.10 mm across the sheet, with consistent hole quality when punch/die clearance is matched to the gauge.
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 Punching Bronze
Customers order CNC Punching 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.
Typical Bronze Parts for CNC Punching
Illustrative examples of CNC Punching Bronze 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.
Louvred cover
- Material
- Bronze
- Size
- 350 × 200 × 1.2 mm
- Key callouts
- Louvre height 4 ±0.3 mm
- Batch
- 2,000 pcs
Louvre tooling forms and cuts in one hit; the direction is set by the airflow spec.
Shim washer
- Material
- Bronze
- Size
- Ø20 / Ø10 × 0.5 mm
- Key callouts
- ID/OD ±0.05 mm, burr < 0.03 mm
- Batch
- 25,000 pcs
Clearance set at 6% of thickness per side to keep the burr under spec without deburring.
Contact blank
- Material
- Bronze
- Size
- 18 × 9 × 0.3 mm
- Key callouts
- Contour ±0.05 mm, burr-free on the contact face
- Batch
- 50,000 pcs
Punched with the burr deliberately on the non-contact side.
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 Punching 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 Punching
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 surface finish is achievable on Bronze with CNC Punching?
Surface finish on Bronze is controlled to your specification; we confirm the achievable Ra against your callout.
What material thickness or size range suits CNC Punching Bronze?
Punching suits Bronze sheet roughly 0.5–6 mm thick, with clearance matched to the gauge.
Can VT machining make custom Bronze parts to my drawing?
Yes. Bronze punching 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 tolerances can you hold for CNC Punching Bronze?
Achievable tolerances for Bronze punching depend on the alloy, geometry and feature size. Punching holds hole-position repeatability to around ±0.10 mm. Exact figures are confirmed against your drawing callouts.
Does CNC Punching Bronze require dedicated tooling?
Punching uses programmable turret tooling; standard tools cover most patterns, with special tools added for unique forms.