CNC Machined Aluminium Gearbox & Transmission Cases
Precisie CNC-bewerking of aluminum gearbox housings, transmission cases, and drivetrain components — from prototype to Productie. Toleranties down to ±0,005 mm, 3/4/5-axis capability, ISO-certified quality. Serving automotive, industrial machinery, robotics, and aerospace clients worldwide.
Kernpunten
- Materiaals: 6061-T6 (general purpose) and 7075-T6 (high-strength) Aluminiumlegerings — full spec table below
- Capabilities: 3-axis to 5-axis CNC-bewerking for housings, covers, bearing seats, and oil passages
- Toleranties: Standard ±0.01 mm, precision ±0,005 mm for bore diameters and gasket surfaces
- Industries: Automotive EV/racing, industrial pumps, robotics actuators, aerospace structures
- Quality: CMM Inspectie, material certification, surface roughness testing on Elke batch
- Turnaround: 7-day prototype lead time, no minimum order quantity
Why Aluminium for Gearbox & Transmission Housings
Aluminium is the dominant material for gearbox and transmission cases in modern manufacturing. Compared to cast iron or steel, aluminum offers three decisive advantages for drivetrain components:
- Weight reduction: Aluminium is 65% lighter than steel — critical for automotive CNC-bewerking Toepassings where every kilogram affects fuel economy and acceleration. A typical aluminum gearbox housing weighs 4-8 kg versus 12-22 kg in cast iron.
- Thermal management: With thermal conductivity of 150-170 W/m·K (3× that of steel), aluminum gearbox cases act as heat sinks, dissipating friction heat from gears and bearings more efficiently. This reduces oil temperature by 10-15°C in sustained operation.
- Corrosion resistance: The natural aluminum oxide layer provides inherent protection against moisture and road salt — no plating required for most environments. For marine or chemical exposure, hard anodiseren adds a 25-50 μm protective layer.
- Machinability: Aluminium’s lower cutting forces (compared to steel or titanium) enable faster cycle times, reducing per-part cost by 30-50% for Productie volumes. Tool life is 3-5× longer than when machining steel alloys.
Best voor: Automotive EV housings, racing transmission cases, industrial pump bodies, and any Toepassing where weight × strength matters.
Avoid when: Extreme wear environments (rock crushers, mining equipment) — consider hardened steel or ductile iron instead.
Aluminiumlegering Selection for Gearbox Toepassings
Choosing the right aluminum grade depends on your strength, weight, and corrosion requirements. Below is a comparison of the most common alloys used in gearbox and transmission manufacturing:
| Alloy | Tensile Strength | Yield Strength | Hardness | Corrosion | Best Toepassing |
|---|---|---|---|---|---|
| 6061-T6 | 310 MPa | 276 MPa | 95 HB | Good | General-purpose housings, covers, mounting flanges |
| 7075-T6 | 572 MPa | 503 MPa | 150 HB | Matig | High-stress transmission cases, racing gearboxes |
| 2024-T3 | 470 MPa | 325 MPa | 120 HB | Poor | Aerospace gearbox structures (with coating) |
| 7050-T7451 | 524 MPa | 469 MPa | 150 HB | Matig | Aerospace transmission housings, stress-corrosion resistant |
| A356-T6 (Cast) | 230 MPa | 165 MPa | 75 HB | Uitstekend | Complex geometry, lower cost for volumes >500 pcs |
For most industrial gearbox Toepassings, 6061-T6 offers the best balance of strength, machinability, and cost. For performance Toepassings where weight savings justify the premium, 7075-T6 delivers near-steel strength at one-third the weight. See our complete aluminum CNC-bewerking guide for detailed speed/feed recommendations.
CNC-bewerking Capabilities for Drivetrain Components
Gearbox housings demand multi-face machining with tight positional Toleranties between bore centers. Our CNC capabilities cover the full range of complexity:
| Machine Type | Max Part Size | Beste voor | Typical Tolerance |
|---|---|---|---|
| 3-Axis CNC | 800×500×500 mm | Flat covers, mounting plates, simple 2-face housings | ±0.01 mm |
| 4-Axis CNC | 600×400×400 mm | Multi-face machining in one setup — shaft bores, oil passages, flange faces | ±0.008 mm |
| 5-Axis CNC | 400×400×350 mm | Complex curved surfaces, impeller housings, aerospace-grade parts | ±0,005 mm |
| CNC-draaien | Ø400×600 mm | Shaft sleeves, bearing housings, circular flanges | ±0,005 mm |
Best voor: Bore diameters from Ø20 to Ø300 mm, bore-to-bore center distance Toleranties of ±0.01 mm, flatness of 0.02 mm/m on sealing surfaces.
Avoid when: Single-setup 3-axis parts under 100×100 mm — our CNC-draaien service may be more cost-effective for small Roterende delen.
Typical Gearbox Parts We Manufacture
Over the past decade, BravoFabs has machined thousands of drivetrain components for clients in 11 countries. The most common parts include:
- Gearbox main housings — Single-piece aluminum bodies with integrated bearing seats, oil galleries, and mounting points. Typical Toleranties: bore Ø ±0.01 mm, flatness 0.02 mm/100 mm.
- Transmission cases (manual & automatic) — Split-case or monoblock designs with internal ribbing for structural rigidity. Common in EV reduction gearboxes and industrial power transmission.
- Bearing housings & retainer plates — Precisie-bored seats for ball and roller bearings, often with threaded mounting holes and dowel pin locations for alignment.
- Sliding sleeves & shift forks — Wear-resistant components machined from 7075-T6 with hard-anodized contact surfaces. Typical hardness: 400-500 HV after anodiseren.
- Oil pump bodies & valve blocks — Complex internal channels for hydraulic fluid routing, pressure-tested to 20+ bar after machining.
- Differential cases & axle housings — Large-diameter bores with cross-drilled lubrication holes. Often machined from 6061-T6 with post-machining T6 Warmtebehandeling.
- Custom motor adapter plates — Precisie-machined interface plates connecting motors to gearboxes, with dowel holes for alignment and threaded bolt patterns.
Surface Afwerkinges & Treatments
Post-machining Oppervlaktebehandelings extend the life and performance of aluminum gearbox components:
| Treatment | Dikte | Hardness | Beste voor |
|---|---|---|---|
| As-Machined | — | 95-150 HB | Prototypes, internal components not exposed to wear |
| Clear anodiseren | 5-15 μm | 200-300 HV | General corrosion protection, cosmetic finish |
| Hard anodiseren | 25-50 μm | 400-500 HV | Wear surfaces, sliding sleeves, outdoor exposure |
| Chemical Film (Alodine) | 1-3 μm | — | Electrical conductivity required, MIL-DTL-5541 |
| Poedercoaten | 60-120 μm | — | Cosmetic outer covers, color-matched branding |
For transmission cases with internal oil passages, we recommend hard anodiseren on all fluid-contact surfaces to prevent erosion from hot oil flow. External surfaces can be left as-machined or anodized for corrosion resistance.
Quality Inspectie Proces
Every gearbox housing undergoes a four-stage Inspectie protocol before shipment:
- CMM Dimensional Inspectie — Bore diameters, center distances, flatness, and perpendicularity verified to ±0.003 mm using a coordinate measuring machine. Full dimensional reports provided with Elke batch.
- Surface Roughness Testing — Gasket sealing surfaces checked with a profilometer. Target: Ra 0.8-1.6 μm for sealing surfaces, Ra 1.6-3.2 μm for non-critical areas.
- Thread Inspectie — Every tapped hole checked with go/no-go thread gauges. Thread classes: 2B/3B (inch) or 6H (metric) as standard.
- Materiaal Certification — Mill test reports (EN 10204 3.1 or equivalent) included with Elke zending, verifying chemical composition and mechanical properties of the raw aluminum billet.
For complete quality documentation on our Inspectie capabilities, see our QC Inspectie devices guide and Kwaliteitscontrole process overview.
Industries & Toepassings
- Automotive: EV motor housings requiring tight stator bore Toleranties; racing transmission cases machined from 7075-T6 billet; differential housings for performance vehicles.
- Industrial Machinery: Pomphuizen for hydraulic systems up to 350 bar; compressor bodies with integrated cooling fins; hydraulic valve manifolds with cross-drilled galleries.
- Robotics: Precisie joint housings with bearing seats for harmonic drive reducers; lightweight actuator bodies for collaborative robots; motor-gearbox interface plates.
- Lucht- en ruimtevaart: Lightweight aluminum gearbox structures for UAV propulsion systems; aircraft actuator housings meeting AS9100 traceability requirements.
- Marine: Corrosion-resistant outdrive housings with hard-anodized protection against saltwater; propeller shaft bearing carriers in 6061-T6.
Why Choose BravoFabs for Gearbox Machining
We are not a general machine shop — drivetrain components are a core competency. Our ISO 9001 certified facility in Dongguan, China has dedicated fixturing for gearbox-class workpieces and processes refined over 10+ years of CNC-bewerking experience.
- ISO 9001 certified facility with full material traceability
- 7-day turnaround on prototypes — from STEP file to first article Inspectie
- No minimum order — 1 piece prototype to 10,000+ Productie run
- Free DFM (Ontwerp for Manufacturing) review identifying cost-saving opportunities before cutting metal
- DHL/FedEx/UPS worldwide shipping with full export documentation
Need a Custom Gearbox Housing? Get a CNC Quote
BravoFabs biedt precision CNC-bewerking for aluminum gearbox housings, transmission cases, and drivetrain components. Our ISO-certified facility delivers tight-tolerance housings for automotive, industrial, and aerospace clients in the US, Germany, and across Europe.
🔗 Gerelateerde productiediensten & artikelen
- CNC-bewerking Service — precision 3/4/5-axis milling and turning for custom metal parts
- CNC-draaidiensten — custom shafts, bushings, and Roterende delen
- CNC-bewerking Aluminium Guide — grades, speeds, feeds, and surface finish recommendations
- QC Inspectie Devices for CNC-bewerking — CMM, Hardheidstesters, and surface roughness tools
- Tolerantienormen in Metaalbewerking — ISO 2768, GD&T, and when to use each