01
Tolerance drift on long runs
Brass cuts fast and heats fast. When the shop does not compensate for thermal growth on a 10,000-part run, bore diameters creep outside the print and the whole lot gets sorted by hand.
Brass CNC Machining
High Precision Brass CNC Machining Parts
GreatLight machines high precision brass CNC parts from C36000, C27400 and C28000 bar stock, holding ±0.005 mm and inspecting 100% of parts before shipment. Send a drawing and get a quote with a free DFM analysis within 12 hours.
Held to ±0.005 mmRa 0.2–0.8 μm finishFrom one piece upward100% inspectionISO 9001:201512-hour quote
127High-precision CNC machines
16Simultaneous 5-axis centers
0.005 mmTolerance held on brass
3–5 daysTypical shipping window
Where brass jobs go wrong
Four problems that kill a brass part
Most brass failures show up in inspection or at the customer's assembly line, not on the machine.
02
Tool marks on visible faces
C36000 machines easily, so operators push feed rates. The result is chatter and tool marks on a decorative face that no amount of polishing will hide without rounding the edge.
03
Dezincification after plating
Brass that sits in a plating line too long can lose zinc at the surface. Threads then pit and the part fails a salt-spray check weeks after it left the shop.
04
Late prototypes
A design review is scheduled for Friday. The brass manifold was promised Tuesday and the shop went quiet. Now the whole team is waiting on one part.
How we hold brass
Cutting brass to print, not to feel
Three things decide whether a brass part comes off the machine correct.
Thermal control
We cut brass cool and measure it warm
Brass conducts heat away from the cut quickly, which is why it machines so well. That same property makes it grow during a long run. We run C36000 at conservative surface speeds, keep coolant on the part, and let the workpiece stabilize before the in-process gauge touches it.
On a 10,000-part run we log the first, middle and last article. If a bore drifts 0.008 mm across the shift, we adjust the offset before it reaches the limit rather than sorting the lot afterward.
- 1Conservative speedsLower surface speed keeps the part near room temperature.
- 2Logged articlesFirst, middle and last part measured every shift.
- 3Offset correctionCompensation applied while the run is still in tolerance.
Finish and edges
Sharp corners are a drawing note, not a default
Brass burrs form fast because the material is soft. On a connector shell or a decorative bezel, a 0.1 mm burr is a reject. We control it with tool geometry, a finishing pass and a defined edge break, then check the edge under magnification.
Where the print calls for a decorative face, we leave stock for a light finishing pass instead of polishing the tool marks away. Polishing rounds edges. A finishing cut does not.
- 1Defined edge breakCorner radius or chamfer set on the print, not left to the operator.
- 2Finishing passLight cut leaves Ra 0.8–1.6 μm without rounding.
- 3Edge inspectionBurrs checked under magnification before the lot moves on.
Grade selection
Which brass grade fits the part
Grade choice drives machinability, corrosion behavior and cost.
| Grade | Machinability | Typical use |
|---|---|---|
| C36000 | Excellent, free-cutting | High-volume turned fittings, connectors |
| C27400 | Good, stronger | Valve bodies, load-bearing bushings |
| C28000 | Moderate | Decorative and plumbing hardware |
| C110 | Good, high conductivity | Electrical contacts, bus bars |
| Beryllium copper | Moderate, spring temper | Spring contacts, non-sparking tools |
What we run
Brass machining services
One shop for the turned part, the milled housing and the finish.
01
CNC Turning
Swiss-type and fixed-head lathes for brass fittings, bushings and threaded connectors, down to Ø1 mm features.
02
3-Axis Milling
Flat housings, plates and manifolds. 27 three-axis machines handle the straightforward geometry at volume.
03
4-Axis Milling
Multi-face parts machined in one setup, so hole-to-hole position stays consistent without re-fixturing.
04
5-Axis Machining
16 simultaneous 5-axis centers for brass parts with compound angles, undercuts or deep cavities.
05
Mill-Turn
16 mill-turn centers combine turning and milling, cutting handling steps on parts that need both.
06
Surface Finishing
Nickel, silver and gold plating, bead blasting, tumbling, brushing and laser marking.
Scope
What a brass order includes
Every brass job carries the same baseline, whatever the quantity.
| Item | What you get |
|---|---|
| Tolerance | ±0.005 mm on critical features, ±0.0002 in |
| Surface finish | Ra 0.2–0.8 μm fine, Ra 0.8–1.6 μm standard |
| Size range | Up to 4,000 mm maximum processing size |
| Quantity | From one prototype to 10,000+ part runs |
| Inspection | Raw material check, in-process monitoring, final inspection |
| Reports | Inspection reports available on request |
Why GreatLight
Six reasons brass buyers stay
Data, not adjectives.
15Y
Machining since 2011
Fifteen years cutting non-ferrous parts in Dongguan, with a second plant in Singapore.
127
CNC machines
Turning, milling and mill-turn capacity under one roof, so a brass assembly does not get split across vendors.
16
5-axis centers
Compound-angle brass work that three-axis setups cannot reach without extra fixtures.
99.99%
Qualification rate
Measured across shipped lots, backed by 100% inspection before shipment.
12 h
Quote turnaround
Drawing in, quotation and free DFM analysis back within 12 hours.
<2%
Late-delivery risk
Historical late-delivery probability below 2% across production orders.
7,600 m²Manufacturing space
3Wholly-owned plants
150Technicians
4Quality certifications
Industry fit
Where brass parts ship
Electronics
Connector shells and RF housings. Brass chosen for conductivity and shielding.
- Ra 0.8–1.6 μm
- Edge break controlled
Automotive & EV
Terminals, bus bars and sensor bodies, run under IATF 16949:2016 process control.
- IATF 16949:2016
- 100% inspection
Medical Devices
Instrument components and fluid fittings in lead-free brass grades.
- ISO 13485:2016
- Inspection reports
Industrial Machinery
Valve bodies, bushings and threaded adapters, turned and milled in one order.
- ±0.005 mm
- Mill-turn capability
FAQs
Brass machining questions
Which brass grade should I specify?
For turned parts at volume, C36000 is the default. It is free-cutting, so cycle times stay low and finishes come out clean.
Choose C27400 when the part carries load. It is stronger and machines almost as well. C28000 and C110 appear when corrosion resistance or conductivity drives the design.
Can you machine lead-free brass?
Yes. Lead-free grades machine differently from C36000. They produce longer chips, so we adjust feeds, speeds and chip-breaking geometry.
Expect slightly longer cycle times than the equivalent C36000 part. On a prototype run the difference is small; on a 10,000-part run it shows up in the price.
What tolerance can you hold on brass?
We hold ±0.005 mm on critical features, which is ±0.0002 in. That applies to bores, journals and mating diameters on turned parts.
Tolerance is a cost driver. If a face is cosmetic, specify Ra 0.8–1.6 μm and leave the dimension open. Tightening everything on the print raises the price without improving the part.
How do you stop brass from tarnishing?
Bare brass oxidizes in humid air. A clear lacquer, nickel or silver plate, or a sealed bag with desiccant will hold appearance in storage.
We apply the finish you specify. If the parts will sit for months before assembly, tell us and we will recommend a barrier finish rather than shipping bare.
Do you offer no minimum order quantity?
Correct. One prototype and a 10,000-part run both go through the same process. The setup cost is spread over fewer parts on a single piece, and that shows in the unit price.
Prototype parts typically ship in 3–5 days once the drawing is released to production.
What files do you need for a quote?
A STEP or IGES model plus a 2D drawing with tolerances, material grade and finish. The 2D print is what we inspect against.
If a feature is critical, mark it. We will flag anything in the DFM analysis that adds cost without adding function.
How is my design kept confidential?
Uploads are secure and confidential. We sign an NDA on request before reviewing drawings.
If you need the agreement in place first, send it through the contact page and we will return it signed.
Can you assemble brass parts with other components?
Yes. We machine brass alongside aluminum, stainless and plastic, so a mixed-material assembly can come from one shop.
Press fits, threaded joints and laser-marked sub-assemblies are all handled before shipment.
Send your brass drawing
Upload a STEP file and a 2D print. A quotation and free DFM analysis come back within 12 hours, no minimum order quantity.
12-hour quote100% inspectionNo minimum order quantityNDA on request
