Dimensional Tolerance
±0.01 mm
Achieved with tooling and parameters developed specifically for gummy materials, plus real-time thermal compensation.
Copper & Brass · Prototype to Mass Production
Precision Copper & Brass CNC Machining Services | Custom Copper Parts
Rapid Model offers custom copper alloy components. Services cover rapid prototyping and mass production. Expert processing techniques ensure optimal performance for critical applications. Global shipping is available with express options.
- Tolerances to ±0.01 mm on gummy, heat-sensitive copper alloys
- Conductivity verified above 99% IACS on critical electrical parts
- C11000 / C10100 / C36000 / C26000 / C93200 / C95400 with mill certification
10+Dedicated Machines
5–10 DayTypical Lead Time
12hrExpert Quoting
98%Conductivity Retention
Measured, Not Claimed
The Numbers Behind Every Copper Part
Surface Finish
Ra ≤ 0.8 µm
Critical for electrical contacts, RF shielding and high-vacuum sealing surfaces. Super-mirror down to Ra 0.05 µm on request.
Quality & Traceability
ISO 9001:2015
Full material certification for C10200, C36000 and the rest of the range, with 100% conductivity testing on critical parts.
Copper Machining Expertise
Precision Copper & Brass CNC Machining Capabilities
Specialised solutions for high-conductivity, thermal management and complex corrosion-resistant copper components.
01
Precision for Electrical Parts
Machining busbars, connectors and terminals to strict tolerances while holding above 98% IACS conductivity.
- Low-stress machining
- Burr-free edges
02
Thermal Solution Machining
Producing complex heat sinks, cold plates and spreaders with optimised fin geometry and flatness.
- High aspect-ratio fins
- Vacuum brazing ready
03
Prototype to Production
Fast-turn CNC prototyping for RF components, waveguides and EDM electrodes in 2–5 days.
- DFM for copper
- Material grade advice
04
High-Volume Copper Parts
Efficient production of brass fittings, plumbing components and decorative hardware with consistent quality.
- Swiss screw machining
- Automated deburring
05
Advanced Multi-Axis Machining
5-axis capability for complex one-piece copper components such as induction coils and nozzle blocks.
- Single-setup efficiency
- Smooth contour finishes
06
Full Copper Alloy Range
Stock and machining expertise across high-conductivity copper, free-cutting brass, cartridge brass, tin bronze and aluminium bronze.
- Alloy property matching
- Certified mill reports
Our Copper Work
CNC Machined Copper & Brass Parts Gallery
Explore our precision-machined copper alloy components and get your custom copper parts.
Copper Alloy Selection Guide
Common Materials Used for Copper Machining
Six of the most widely used copper materials in CNC machining, selected for conductivity, machinability, strength and wear resistance.
High Conductivity Copper
- C11000 — ETP / T2 Copper
- Excellent electrical and thermal conductivity, widely used for electrodes and bus bars.
- C10100 — Oxygen-Free Copper
- Ultra-high purity copper for vacuum, aerospace and semiconductor components.
Free-Machining Brass
- C36000 — Free-Cutting Brass / H59
- Best machinability in the range, and the standard material for fittings, shafts and fasteners.
- C26000 — Cartridge Brass / H70
- Good strength and formability, suitable for thin-wall and decorative parts.
Bronze & High-Strength Alloys
- C93200 — Tin Bronze / SAE 660
- Excellent wear resistance, commonly used for bushings and bearings.
- C95400 — Aluminium Bronze
- High strength and corrosion resistance, ideal for marine and valve components.
Our Processes
Copper-Specific CNC Machining Processes
We use specialised techniques and tooling to overcome the challenges of machining copper alloys — material gumminess and heat sensitivity — and deliver precision components with clean surface quality.
Precision Copper Milling
Sharp, polished tooling and high-speed strategies to prevent material adhesion and achieve fine finishes on electrical and thermal components.
CNC Turning of Brass & Copper
Expert turning of rod and bar into connectors, fittings and shafts, with live tooling for cross-drilling and milling features.
Finishing & Plating
Post-machining services including polishing, plating in nickel, silver, gold or tin, passivation and anti-tarnish treatments.
Industry Applications
Copper CNC Machining: Industry Challenges & Solutions
- Power Electronics
- Automotive (EV/Hybrid)
- Semiconductor
- Telecom & RF
Project Specs
- MaterialC11000 (ETP copper)
- Key spec>99% IACS conductivity
- Tolerances±0.1 mm on slot positions
High-Current Inverter Busbar Assembly
Conductivity PreservationThe Technical Challenge
The main challenge was holding extreme dimensional accuracy across a large, thin copper plate while preserving its maximum electrical conductivity. Any excess heat input or work hardening during machining degrades conductivity. On top of that, the long narrow slots for the power modules needed absolute precision and burr-free edges to prevent short circuits.
Our Engineering Solution
We combined sharp, polished carbide end mills with a high-speed, low-depth-of-cut milling strategy to minimise heat and work hardening. The part was fixtured on a custom vacuum plate to avoid clamping distortion. A final in-machine deburring pass with a specialised tool left every slot edge smooth and safe, and post-machining conductivity testing confirmed above 99% IACS retention.
>99% IACSConductivity
Burr-FreeSlot Edges
0.2 mmFlatness
Project Specs
- MaterialPure copper, rectangular bar
- GeometryComplex 3D bent form
- RequirementPrecision end features
EV Motor Stator Hairpin (Pre-Form Machining)
Pre-Bend Datum ControlThe Technical Challenge
The raw copper hairpins are bent into complex 3D shapes after machining. The challenge was to machine the precise mating features — chamfers, slots and profiles — on the ends of the soft rectangular copper bar before the bending process, positioned accurately enough that every hairpin would still align correctly in the stator stack once bent.
Our Engineering Solution
We developed a dedicated multi-stage fixture that held the rectangular bar at the exact datum points used by the bending machine. Using synchronised 3+2 axis machining, both ends were cut in a single setup, which guaranteed symmetry and positional accuracy. Tool geometry was chosen specifically to avoid burrs that would interfere with the downstream insulation process.
±0.03 mmLocation
MirrorSymmetry
ZeroBending Interference
Project Specs
- MaterialC10100 (oxygen-free copper)
- SurfaceSuper-mirror finish
- CleanlinessHigh-vacuum compatible
Semiconductor Wafer Handling Component
Mirror Finish on Soft CopperThe Technical Challenge
The part needed a surface finish of Ra below 0.05 µm across large flat areas, which is extremely demanding on soft ductile copper because it scratches easily and shows every tool mark. The part also had to be completely free of oils, fingerprints and embedded particles to avoid contamination inside a high-vacuum semiconductor tool.
Our Engineering Solution
Machining ran in a controlled clean area using single-crystal diamond turning tools on an ultra-precision lathe, achieving the mirror finish directly from the machine and minimising post-processing. Only high-purity semi-aqueous coolants were used, fully removed in a multi-stage ultrasonic clean, followed by vacuum baking and Class 100 cleanroom packaging.
Ra < 0.05 µmFinish
Class 100Packaging
ZeroParticulate
Project Specs
- MaterialC36000 brass, nickel plated
- FeaturesDeep, small-diameter holes
- RequirementImpedance control
High-Frequency RF Connector Body
Impedance-Critical BoresThe Technical Challenge
The part needed extremely precise internal diameters and surface finishes to maintain a specific characteristic impedance. Drilling deep, small-diameter holes in brass at a high length-to-diameter ratio risked tool deflection and poor finish. Any internal scratch or diameter variation causes signal reflection and loss, degrading performance at GHz frequencies.
Our Engineering Solution
We combined gun drilling for straightness in the deep holes with precision boring and honing to reach the final diameter and finish, all tightly controlled by in-process gauging. Internal surfaces were micro-polished before nickel plating to give a flawless, low-loss conductive path, and impedance testing on sample parts verified performance before release.
50 Ω ±1Impedance
Ra 0.4 µmInternal Finish
< −30 dBReturn Loss
Material Properties Guide
Copper Alloy Comparison for CNC Machining
Compare conductivity, machinability, strength and corrosion resistance to pick the right copper alloy for your application.
- Performance Comparison
- Temper & Condition
- Surface & Plating
- Design for Copper
| Copper Alloy | Conductivity (% IACS) | Machinability Rating | Typical Strength | Primary Applications |
|---|---|---|---|---|
| C11000 (ETP Copper) | >100% | 20% (gummy) | Medium | Busbars, electrical contacts, heat sinks |
| C10100 (OFC) | >101% | 20% | Medium | Semiconductors, high-vacuum, particle accelerators |
| C36000 (Free-Cutting Brass) | ~28% | 100% (reference) | Good | Fittings, valves, precision screw machine parts |
| C26000 (70/30 Brass) | ~28% | 30% | Medium-High | Ammunition components, fasteners, decorative hardware |
| C93200 (Bearing Bronze) | ~12% | 70% | High | Bearings, bushings, washers (SAE 660) |
| C95400 (Aluminum Bronze) | ~13% | 20% (tough) | Very High | Heavy-duty gears, marine hardware, wear plates |
| Alloy | Common Tempers / Conditions | Yield Strength (MPa) Typical | Machining Advice |
|---|---|---|---|
| C11000 / C10100 | H02 (½ hard), H04 (hard) | 250–350 | High speeds, sharp tools. Use H04 for cleaner chip breaking. |
| C36000 | H02 (½ hard) | 200–310 | Industry standard for machinability. Excellent surface finish. |
| C26000 | H02 (½ hard), annealed | 110–380 | Prone to stringy chips; requires chip breakers. Great for cold forming. |
| C93200 | As cast / M07 | 125–170 | Contains lead for self-lubrication; machines very well. |
| C95400 | As cast, heat treated (TQ50) | 300–500 | Very tough and abrasive. Requires carbide tooling and rigid setups. |
| Copper Alloy | Polishability | Nickel Plating | Silver / Gold Plating | Notes |
|---|---|---|---|---|
| C11000 / C10100 | Excellent | Excellent | Excellent | High purity allows superior electroplating adhesion. |
| C36000 / C26000 | Excellent | Excellent | Excellent | Commonly used for decorative finishes. C26000 is more ductile. |
| C93200 (Bronze) | Good | Fair | Fair | Porous nature can affect plating; often used bare with oil. |
| C95400 (Al-Bronze) | Fair | Poor | Poor | Naturally forms a protective alumina layer; hard to plate. |
| Design Factor | General Guideline | High-Precision Guideline | Reasoning & Recommendation |
|---|---|---|---|
| Minimum Wall Thickness | 0.5 mm | 0.8 mm | Pure copper is soft; C95400 is tough but needs rigidity. |
| Internal Sharp Corners | R ≥ 0.5 mm | R ≥ 1.0 mm | Reduces burr formation in ductile alloys such as C11000 and C26000. |
| Thread Depth | 1.5 × dia | 2.5 × dia | C36000 taps easily; C95400 requires heavy-duty taps. |
| Hole Tolerance | ±0.05 mm | H7 / G6 | Essential for C93200 bearing press-fits to ensure correct clearance. |
Material Selection Tip
Choose C11000 / C10100 for maximum electrical and thermal conductivity.
Where conductivity is secondary and the geometry is complex, C36000 brass
offers the lowest cost because it machines at high speed.
Wear Resistance
C93200 is the go-to for standard bushings because of its anti-friction
properties. For high-load, high-impact environments, C95400 aluminium bronze
provides superior mechanical strength and corrosion resistance.
Manufacturing Note
Pure coppers (C11000 / C10100) are gummy during CNC milling, so expect higher
deburring cost than on C36000.
Streamlined Process
Your Copper Parts, From Quote to Delivery
Our dedicated process for copper components ensures expert handling from initial design review through final inspection, so parts meet your electrical, thermal and mechanical specifications.
01
Quote & DFM Review
Upload your drawings for pricing and a copper-specific manufacturability review.
02
Alloy & Tooling Plan
We confirm the grade, temper and tooling strategy before any metal moves.
03
Precision Machining
Cut by specialists using copper-optimised parameters and tooling.
04
Stringent Quality Check
Dimensional inspection, conductivity testing where required, and surface finish verification.
05
Finishing & Shipment
Apply the specified plating or finish, then pack and ship with full documentation.
FAQ
Copper CNC Machining Questions Answered
-
What are the main benefits of CNC machining copper parts?
CNC machined copper parts offer unmatched electrical and thermal conductivity, excellent corrosion resistance, inherent antimicrobial properties, and good machinability in certain alloys such as brass. They are essential for power distribution, heat management, RF components and decorative applications.
-
Which copper alloy is easiest to machine?
C36000 (free-cutting brass) is the industry standard for machinability, rated at 100%. It contains lead, which improves chip formation. For lead-free options with good machinability, consider C46400 (naval brass) or C48500 (leaded free-machining brass).
-
How do you prevent burrs when machining soft copper?
We use several strategies together: sharp, polished tooling with specific geometries; high-speed, low-feed parameters; in-process deburring tools; and secondary processes such as thermal energy method, vibratory finishing or chemical deburring to reach burr-free edges as specified.
-
Can you machine pure copper (C11000) to tight tolerances?
Yes. Although pure copper is gummy, we hold ±0.01 mm on critical features using specialised sharp tooling, rigid setups, controlled coolants and machining strategies that minimise heat and material pull. Harder tempers such as H04 are often easier to hold to tolerance than annealed copper.
-
What surface finishes and platings are available for copper parts?
Finishes include polishing, brushing and buffing. Plating options are extensive: nickel for hardness and as a barrier, silver for the highest conductivity, gold for corrosion resistance on contacts, tin for solderability, and passivation as a clear anti-tarnish treatment. We recommend based on your application.
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Do you provide material certifications for copper alloys?
Yes. We supply full traceability and material test reports or certificates of conformity for all copper alloys, certifying composition, temper and physical properties. For electrical grades we can also provide conductivity test reports on request.
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What industries most commonly use CNC machined copper components?
Key industries include electrical and power (busbars, connectors), automotive and EV (battery components, hairpins), telecommunications (RF connectors, waveguides), semiconductor (chuck components, heaters), plumbing and marine (fittings, valves), and aerospace (conductive components).
-
Is machining copper alloy more difficult than pure copper?
Yes, generally. Copper alloys often contain added elements that raise hardness and strength, which makes cutting and shaping more demanding on tooling and requires more rigid setups and more conservative parameters.
-
What determines how difficult a copper part is to machine?
The difficulty depends on alloy composition, since higher alloying content increases hardness and toughness; material hardness, because harder alloys wear tools faster; thermal conductivity, since lower conductivity causes heat build-up; ductility and toughness, which affect chip formation and tool wear; and the surface finish requirement, because tighter tolerances need more precise machining.
Send us your copper part. Get a quote in 12 hours.
Upload your CAD files with tolerances, alloy grade and plating requirements, and our engineers will come back with pricing, lead time and free DFM feedback.
