Chinese Alum CNC Processing Solutions

Aluminium is not one material on a machine. 6061-T6 machines cleanly, holds thin walls and takes anodizing well, which is why it covers most brackets, housings and fixtures. 7075 cuts harder, deflects more under load, and is the choice when strength matters more than tool life. 2024 has good fatigue behaviour but is less corrosion resistant, so it usually ends up plated or painted.

For die-cast or high-volume parts, ADC12 is a different conversation. It is designed for casting, not for hogging out of billet, and its surface finish after machining is less uniform. If you send a casting drawing expecting billet tolerances, the quote will be wrong.

Stock form drives the setup. Plate is stable and easy to fixture. Extrusion is cheaper per kilo but has internal stress and a grain direction, so a long thin rail may move after the first cut. Forgings are strong but need more stock removal and a roughing pass before finishing. Tell us the stock form and we can plan the operations around it.

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  6061-T6General parts, thin walls, anodized finishes. Default for most work.
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  7075High-strength structural parts. Expect more tool wear and spring passes.
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  2024Fatigue-loaded parts. Usually plated or coated after machining.
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  5052 / 5083Formed sheet and welded assemblies rather than heavy milling.

A five-axis center earns its cost when a part has features on several faces, deep pockets with non-vertical walls, or a contoured surface that would need many re-fixturing steps. Machining five faces in one setup removes the stack-up error that comes from flipping a part four times on a three-axis mill. On a part with a true position callout across two faces, that difference decides whether the part passes.

Five-axis is not always faster. For a flat plate with holes and a profile, a three-axis machine with a good fixture will beat it on cycle time and on cost. We keep 27 three-axis machines and 12 four-axis mills for exactly that work. The rule we use: if the part can be reached in one or two setups on three axes, do that.

Our largest 5-axis travel is 4,000 × 400 × 150 mm. Medium frames run 750 × 1,150 × 550 mm and 600 × 600 × 600 mm. Compact work sits on 500 × 500 × 450 mm or 500 × 310 × 200 mm tables, and we have a Ø400 mm rotary table for round and cylindrical parts. If a part is longer than 4,000 mm, it is a different process, not a bigger machine.

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  One-setup partsUse 5-axis when datums must stay aligned across faces.
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  Deep 3D contoursBall-nose finishing on a tilting head cuts steps and hand work.
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  Flat plates and covers3-axis with a plate fixture is cheaper and faster.
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  Long thin railsFixture support matters more than axis count. Stress relief helps.

Anodizing builds a layer on the surface, so a hardcoat on a Ø20 mm bore can close it by more than you expect. If a mating diameter is called out to ±0.005 mm, tell us before finishing. We mask or machine the critical surfaces after coating. Clear and colour anodizing are thinner and easier to manage than hardcoat, but none of them are zero.

Electroless nickel adds a more even layer than anodizing and reaches into holes and recesses, which is why it shows up on wear surfaces and RF housings. Zinc, silver and gold plating are used for conductivity and corrosion, mainly on connector and electronics parts.

Mechanical finishes change the look without changing size much. Bead blasting gives a matte, uniform surface and hides tool marks. Tumbling softens edges on small parts in bulk. Brushing leaves a directional grain, which means the direction has to be specified or you get whatever the operator chose. Laser marking is available with a minimum character height of 1.5 mm; smaller text fills in and becomes unreadable.

Every job starts with a raw material check. Alloy grade matters, and a batch of unmarked plate is not worth the risk. During machining we monitor in process: tool wear on long cycles, first-article dimensions on a new setup, and adjustments before the whole run drifts out of tolerance.

Final inspection is 100% before shipment. Critical dimensions go on a CMM, not on calipers. For simple features, calibrated micrometers and bore gauges are enough and they are faster. Inspection reports are available on request, and for regulated work we can structure the report around the drawing callouts.

Our plants hold ISO 9001:2015, IATF 16949:2016, ISO 13485:2016 and ISO 27001:2022. The first three cover quality systems for general, automotive and medical work. ISO 27001 covers how drawings and files are handled, which matters if your part is unannounced. Uploads are treated as confidential, and an NDA is available on request.

The qualification rate we track is 99.99%. That number is only meaningful with the inspection behind it, so it is reported against parts that passed final inspection, not against parts that left the machine.

A STEP file plus a 2D drawing with tolerances, datums and finish callouts is the baseline. If you only have a 3D model, we can still quote, but we will assume general tolerances and you should expect a note about which features need tighter control. Mark the critical dimensions. It changes the setup and the inspection plan.

Tell us the quantity and the stock form. One prototype and a 10,000-piece run are different processes: the prototype may be machined complete from billet, while the run may use fixtures, soft jaws and a first-article approval step. We have no minimum order quantity, so one part is fine, but the per-part cost will reflect the setup.

Quotation and a free DFM analysis come back within 12 hours. The DFM note flags things that will cost you money: a pocket too deep for the tool diameter, a wall too thin to hold, a tolerance that cannot be inspected, or a finish that conflicts with a mating dimension. Production can start within 24 hours of approval, and parts typically ship in 3–5 days. Historical late-delivery probability is below 2%.

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  3D modelSTEP or Parasolid. Native CAD files are fine too.
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  2D drawingTolerances, datums, surface finish, thread callouts.
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  QuantityPrototype, bridge, or production volume.
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  Finish specAnodize type, colour, masking areas, marking text.