CNC Boring Brass

Looking for reliable CNC Boring Brass? VT machining manufactures Brass parts to tight tolerances and consistent quality. Brass is free-machining, good conductivity, attractive finish, so the process is set up specifically for the material.

CNC Boring Brass at VT machining
CNC Boring Brass — produced in-house at VT machining

CNC Boring Capability for Brass

  • Bore tolerance to IT6
  • Roundness within 0.005 mm
  • Fine boring heads
  • Large-diameter capability

Brass Material Data

Brass — typical properties, quoted for C36000
Density8.50 g/cm³
Tensile strength340–470 MPa
Yield strength (0.2%)125–310 MPa
Hardness78–130 HB
Melting point885–900 °C
Thermal conductivity115 W/m·K
Thermal expansion20.5 ×10⁻⁶/K
Electrical conductivity26%
Machinability (C36000 = 100%)100% (the benchmark)
Grades we runC36000 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.

Machining Brass — what actually causes trouble

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 Boring Brass Works

The Brass bar or billet rotates in the spindle while single-point tools shape outer diameters, bores, faces, grooves and threads. Constant surface speed control keeps cutting conditions stable from large to small diameters.

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 Boring Brass

CNC Boring Brass — achievable tolerances
FeatureStandardPrecision
Outside diameter±0.05 mm±0.005 mm
Bore diameterH9H6
Length / shoulder position±0.10 mm±0.020 mm
Concentricity OD to ID0.05 mm TIR0.010 mm TIR
Roundness0.02 mm0.005 mm
Thread class6g / 2A4h / 3A
Surface finish, as turnedRa 1.6 µmRa 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.

CNC Boring Tolerances & Surface Finish

Turned Brass holds diameter tolerances to about ±0.005 mm with concentricity within 0.01 mm and good roundness. Turned finishes of Ra 0.4–0.8 µm are achievable with finishing passes and sharp tooling.

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.

Design Tips for CNC Boring Brass

We are happy to suggest design tweaks that improve manufacturability. Consistent diameters, standard thread forms and avoiding extremely long, slender features help Brass turned parts stay concentric and economical. If you send your model early, we will return practical DFM feedback before you commit to production.

CNC Boring 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 Brass part to print. Inspection reports, material certificates and first-article documentation can be supplied on request.

Secondary Operations & Finishing

Finished Brass 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.

Working with Brass

As a material, Brass is free-machining, good conductivity, attractive finish. 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.

Applications of CNC Boring Brass

Customers order CNC Boring Brass 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 Boring Brass

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 Brass

Three representative CNC Boring Brass 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.

Nozzle body

Material
Brass
Size
Ø12 × 46 mm
Key callouts
Ø0.6 mm orifice ±0.01 mm, internal taper 20°
Batch
600 pcs

Orifice EDM-drilled after turning; a drill wanders at that diameter.

Bearing spacer

Material
Brass
Size
Ø35 / Ø22 × 9 mm
Key callouts
Thickness ±0.005 mm, parallelism 0.005 mm
Batch
4,000 pcs

Turned then double-disc ground — thickness this tight is not a lathe job.

Valve seat

Material
Brass
Size
Ø28 × 14 mm
Key callouts
Seat angle 45° ±0.1°, roundness 0.005 mm, Ra 0.2 µm
Batch
800 pcs

Seat finished with a single-point diamond pass, no interruption.

Finishing Options for Brass

Finishing options available with this material
FinishThickness / effectWhy it gets specified
Nickel plate5–15 µmHard, bright, corrosion resistant
Chrome plate0.3–1 µmDecorative, over nickel
Clear lacquer10–20 µmStops the natural tarnish
Tin plate3–15 µmSolderable contacts
Deburr / edge break0.05–0.3 mmAll parts unless the drawing says otherwise
Bead blastRa 1.6–3.2 µmUniform matt finish, hides tool marks
Laser markingPart number, lot code, data matrix
Free — no sign-up

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.

Open the 3D + 2D Builder

What We Need to Quote CNC Boring 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 Boring

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 Quote

Frequently Asked Questions

Can VT machining make custom Brass parts to my drawing?

Yes. Brass Brass turning 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.

How clean are the edges produced by CNC Boring on Brass?

Machined Brass edges are clean and to specification; edge-break or deburring is added when your drawing calls for it.

Does CNC Boring Brass require dedicated tooling?

Most Brass turning 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 Boring Brass?

Achievable tolerances for Brass turning depend on the alloy, geometry and feature size. Turning holds diameter tolerances to around ±0.005 mm with concentricity within 0.01 mm. Exact figures are confirmed against your drawing callouts.

What surface finish is achievable on Brass with CNC Boring?

Surface finish on Brass is controlled to your specification; we confirm the achievable Ra against your callout.