Die Casting Services: Aluminium & Zinc Precision Castings from Tooling to Finished Assembly
One Supply Chain, Not Five Vendors
Most buyers of die casting parts do not have a casting problem. They have a coordination problem — a foundry in one place, a machine shop in another, an anodiser somewhere else, and an assembly house at the end. Every handover is a lead-time buffer, a freight leg, and a party who can blame the party before them.
Our die casting services run the complete chain in one facility under one quality system: design review, mould flow simulation, tool manufacture, casting, machining, finishing, inspection and assembly. One contract, one engineer to call, one organisation accountable when something needs fixing.
Casting Capabilities
Machine Range
| Capability | Specification |
| Clamp force | 250 – 1,600 tons |
| Process | Cold chamber (aluminium) · Hot chamber (zinc) |
| Part weight | 20 g – 25 kg |
| Maximum projected area | Up to approx. 400 in² |
| Cavity configuration | Single, multi-cavity and family tools |
| Vacuum assist | Available on nominated cells |
| Local squeeze pressurisation | Available for pressure-tight parts |
Clamp force is selected by projected area, not part weight. Aluminium requires roughly 2–4 tons per square inch of projected area including the runner system, so a component with 300 in² projected area is assigned to a 600–1,200 ton machine with margin against parting-line flash.
Achievable Tolerances
| Feature | As-Cast | Post-Machined |
| Linear, per 25 mm | ±0.10 mm | ±0.02 mm |
| Across parting line | ±0.25 mm | — |
| Flatness, per 100 mm | 0.15 mm | 0.02 mm |
| Hole true position | ⌀0.30 mm | ⌀0.05 mm |
| Surface roughness | Ra 1.6 – 3.2 µm | Ra 0.8 µm |
| Minimum wall — aluminium | 1.2 mm | — |
| Minimum wall — zinc | 0.4 mm | — |
| Draft angle | 1° external, 1.5–2° internal | — |
General tolerances follow NADCA Product Standards. We recommend applying tight tolerances only to critical-to-function features — bores, sealing faces, threaded ports and mounting datums — and leaving remaining dimensions at general casting tolerance. A drawing carrying ±0.05 mm on every dimension forces machining of every surface and can double piece price with no functional gain.
Alloys We Run
| Alloy | Si % | Cu % | Key Characteristics | Typical Use |
| A380 / ADC10 | 7.5–9.5 | 3.0–4.0 | Best all-round castability, strength and machinability | Housings, gearboxes, enclosures |
| A360 | 9.0–10.0 | ≤0.6 | Superior corrosion resistance, higher ductility | Marine, outdoor equipment |
| A413 / ADC12 | 11.0–13.0 | ≤1.0 | Highest fluidity, naturally pressure-tight | Manifolds, hydraulic bodies |
| A356 (gravity, T6) | 6.5–7.5 | ≤0.25 | Heat treatable to 200+ MPa yield | Structural components |
| ZAMAK 3 / 5 | — | — | Walls to 0.4 mm, plating-ready surface | Small detailed and decorative parts |
Two selection notes we raise during aluminum alloy processing manufacturing review, because they cause more late-stage surprises than any other material issue:
A380 does not anodise bright. Its 3–4% copper produces a mottled dark grey film rather than clean silver. Where bright anodised appearance matters, we specify A360 or A413 at design stage — changing alloy after tooling is cut may require gate and thermal re-engineering.
Wrought alloys cannot be cast. If a drawing calls for 6061-T6, that part must be CNC machined from billet or built by aluminum fabrication from extruded profile. 6061 carries only 0.4–0.8% silicon, giving it poor fluidity and a wide freezing range that hot-tears in a steel die. We flag this at quotation rather than substituting silently.
The Production Workflow
1 · RFQ and DFM review — 3–5 days. We return manufacturability feedback with the quotation, not after the order: wall thickness optimisation, draft verification, parting line proposal, gate location and any features that will require side actions.
2 · Mould flow simulation — 1 week. Solidification analysis predicts fill sequence, air entrapment zones and shrinkage-risk regions before steel is cut. Each avoided cavity modification saves three to four weeks of programme time.
3 · Tool design and manufacture — 5–8 weeks. Cavity inserts in nitrided H13 at 44–48 HRC, with conformal cooling circuits and baffles or bubblers in deep core pins.
4 · T1 sampling — 1–2 weeks. Full-dimension inspection report with actual measured values, plus the qualified shot parameters that define the production window.
5 · Production casting. Shot velocity, intensification pressure and fill time recorded per cycle against the qualified window, with automatic quarantine of out-of-window parts.
6 · Trimming and deburring. Runner, gate and overflow removal in a trim press, followed by flash removal on parting lines.
7 · Cnc Machining. Bores, threaded ports, sealing faces and datums brought to ±0.02 mm. Threads are always machined rather than cast — cast threads rarely reach the surface finish required for reliable sealing.
8 · Surface Finishing. Shot blasting, chemical conversion, anodising, Powder Coating, e-coat or plating.
9 · Inspection, assembly and packing. Final dimensional audit, functional testing, insert and seal fitting, then VCI packing for export.
Total: 13–23 weeks from drawing approval to production release for a new tool. Where geometry is still evolving, bridge tooling in P20 delivers real high-pressure process validation in 3–5 weeks at a fraction of production tooling cost.
Surface Finishing Options
| Process | Build Thickness | Primary Benefit |
| Shot / bead blasting | — | Uniform matte finish, deflashing |
| Chemical conversion (Cr³⁺) | 0.5–2 µm | Paint adhesion, electrically conductive |
| Anodising Type II | 5–25 µm | Corrosion and wear resistance, colour |
| Hard anodise Type III | 25–100 µm | Severe wear surfaces |
| Powder coating | 60–120 µm | Colour, UV and impact resistance |
| E-coat | 15–35 µm | Uniform coverage into recesses |
| Plating (Ni / Cr) | 5–25 µm | Decorative bright finish — best on Zinc Casting |
One specification detail worth raising early: anodising is an electrical insulator; chemical film conducts. If a Die Cast housing relies on a bolted joint for chassis ground or on wall continuity for EMI shielding, a fully anodised part breaks that path. We mask grounding pads, or treat them with chemical film only, and record the requirement as a defined zone with a stated resistance limit on the drawing.
Coating thickness also consumes fit clearance. Anodising grows roughly half into the substrate and half outward, so 25 µm hard anodise reduces a bore diameter by around 25 µm. Powder coat at 60–120 µm is far more severe and deposits unevenly, concentrating on edges. Drawings should state whether dimensions apply before or after coating; precision bores are masked and reamed last.
Secondary Operations and Fabrication
Beyond casting and machining we provide the operations that turn a raw casting into a shippable assembly:
Heat treatment
- — T5 artificial ageing for die castings; full T6 available on gravity-cast A356
Insert installation
- — threaded inserts, press-fit bearings, dowels and bushings
Leak and pressure testing
- — air-under-water or helium mass spectrometry to a specified leak rate
Sub-assembly build
- — seals, gaskets, fasteners and mating components fitted and tested
Metal fabrication
- — laser cutting, CNC press brake forming, TIG and MIG welding
That last capability matters more than it appears. Many products are best built as hybrids: a cast body carrying the complex sealed geometry, with custom metal fabrication brackets attached for the mounting interface. Splitting the work this way often removes two side actions from the die, reducing both tooling cost and cycle time. Because both routes run in-house, the tolerance stack-up between cast and fabricated components is analysed by one engineering team rather than disputed between two suppliers.
For low-volume structural fabrication — frames, chassis and enclosure panels — no tooling is required at all and parts ship in one to three weeks.
Quality System and Inspection
Certification: ISO 9001:2015. IATF 16949 capability for automotive supply, with PPAP Level 3 submissions including FMEA, control plan, MSA and capability study.
Inspection capability:
| Equipment | Purpose |
| CMM, calibration traceable to national standard | GD&T verification on critical features |
| Optical emission spectrometer | Per-heat alloy chemistry before melt release |
| X-ray inspection | Internal soundness to ASTM E505 with drawing zone map |
| Leak test equipment | Pressure-tight verification at rated pressure |
| Salt spray chamber (ASTM B117) | Coating corrosion performance |
| Coating thickness gauge | Anodise and powder film verification |
| Surface roughness tester | Ra verification on machined and as-cast faces |
Document package supplied with every shipment: material certificate per heat with OES chemistry, dimensional inspection report with actual measured values, treatment records, NDT results where specified, and a packing list with lot traceability back to heat number and production date.
We treat documentation as a delivery condition rather than an optional extra, because once parts are on a vessel it is the only enforceable record either party has.
Industries and Applications
Automotive and EV — motor housings, gearbox covers, oil pans, structural brackets, battery enclosure components. PPAP submissions, SPC on critical-to-function dimensions and 100% leak testing as standard deliverables.
LED and lighting — street light housings, high-bay bodies, heat sinks. Thermal performance depends on fin geometry and coating choice; a thick powder coat insulates, while thin black anodise raises radiative emissivity.
Telecommunications and electronics — enclosures, RF housings, heat sinks, mounting frames. EMI shielding depends on wall continuity and conductive grounding paths, which is why chemical film zoning is specified rather than left to the coater.
Industrial equipment — pump bodies, valve housings, gear cases, actuator bodies. Pressure-tight parts run with vacuum assist plus local squeeze pressurisation and are 100% leak tested.
Fluid handling — manifolds, elbows, flange adapters and fittings. For pipe fittings manufacturer requirements, threads are machined post-cast and radiographic acceptance is specified per ASTM E505 with a zone map.
Consumer and hardware — appliance components, tool housings, furniture hardware. Small detailed decorative parts typically run in zinc casting for its 0.4 mm wall capability, 500,000+ shot tool life and plating-ready surface.
Why Buyers Consolidate With Us
Engineering feedback before you commit. Every quotation includes DFM comment. A supplier who returns a price with no manufacturability question has priced in the problems they can see and stayed silent about them.
Simulation used as a design tool, not a diagnostic. Mould flow analysis runs before steel is cut, not after a failed T1 trial.
Process data you can hold us to. T1 approval comes with the qualified shot parameters. Production is measured against that window every cycle, which makes drift detectable rather than discovered at your goods-in.
Tooling terms in writing. You own the die once paid. It is asset-tagged, its storage location documented, and it will be released within 30 days of written request without preconditions tied to commercial matters.
One accountable party. Casting, machining, finishing, fabrication and assembly under one quality system removes the situation where each vendor blames the one before them.
Frequently Asked Questions
Q1: What are die casting services?
Die casting services cover the injection of molten metal into a hardened steel die under high pressure to produce net-shape metal parts at volume. A complete service extends well beyond the casting operation itself to include design-for-manufacturability review, mould flow simulation, tool design and manufacture, sampling and validation, production casting with process monitoring, trimming, CNC machining, surface finishing, inspection and assembly. Buying these as one package rather than from separate vendors removes handover delays and gives you a single accountable party.
Q2: What tolerances can die casting achieve?
As-cast tolerance for aluminium high pressure die casting is approximately ±0.10 mm per 25 mm within one die half, widening to ±0.25 mm across the parting line, per NADCA Product Standards. Post-cast CNC machining brings critical features to ±0.02 mm or better. As-cast surface roughness runs Ra 1.6–3.2 µm on cavity-contact faces and Ra 0.8 µm on machined surfaces. Best practice is to tightly tolerance only critical-to-function features and allow general casting tolerance elsewhere.
Q3: What is the minimum order quantity for custom die casting?
Once tooling exists, production batches from 500–1,000 pieces are practical. The real constraint is tooling amortisation rather than batch size, and custom die casting typically becomes cost-competitive above roughly 5,000 pieces per year. For lower volumes or design validation, bridge tooling in P20 steel gives 5,000–20,000 shots at substantially lower upfront cost with a 3–5 week tooling lead time, in exchange for a higher piece price.
Q4: How long does die casting tooling take?
A single-cavity aluminium tool of moderate complexity takes 5–8 weeks from approved drawing to T1 samples, with multi-cavity or heavily cored tools adding 2–4 weeks. Total programme time from drawing approval to production release runs 13–23 weeks including DFM, simulation, sampling, tool tuning and PPAP. The critical path is CNC roughing and EDM finishing of cavity inserts, followed by trial sampling and dimensional tuning.
Q5: Should I choose aluminium or zinc die casting?
Choose zinc casting for components under roughly 500 g requiring walls below 1 mm, fine cosmetic detail or decorative plating. Zinc's hot-chamber process delivers 500,000–1,000,000 shot tool life against aluminium's 200,000–350,000, plus faster cycles and a plating-ready surface. Choose aluminum casting when weight matters at 2.7 g/cm³ against zinc's 6.6, when thermal conductivity is needed for heat dissipation, or when service temperature exceeds 100°C, which is beyond zinc's practical limit.
Q6: Which industries use die cast parts?
Automotive and EV for motor housings and structural brackets; LED and lighting for heat-dissipating housings; telecommunications and electronics for enclosures and RF housings; industrial equipment for pump bodies, valve housings and gear cases; fluid handling for manifolds and fittings; and consumer hardware for appliance and tool components. The common requirement is complex geometry with thin walls at volume — the conditions where die casting outperforms sand casting, fabrication and machining on total cost.
Q7: Can you produce pressure-tight castings?
Yes. Pressure tightness requires three controls working together: vacuum assist to evacuate the cavity below 50 mbar before injection, eliminating gas porosity; local squeeze pressurisation using hydraulic pins driven into heavy sections while the metal is semi-solid, eliminating shrinkage porosity that gating alone cannot feed; and 100% leak testing at rated pressure. We also recommend A413 alloy for its superior fluidity and natural pressure tightness, and radiographic acceptance specified per ASTM E505 with a drawing zone map.
Q8: Do you handle machining and finishing, or only casting?
Both, in-house. CNC machining, heat treatment, all major surface finishing processes, insert installation, leak testing and sub-assembly build run under the same quality system as the casting operation. We also provide metal fabrication — laser cutting, press brake forming and welding — which allows hybrid assemblies where a cast body is combined with fabricated brackets. Keeping both routes in-house means tolerance stack-up between cast and fabricated components is engineered rather than disputed.