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Custom Die Casting Services: Aluminium, Zinc & Magnesium Components with In-House Tool & Die

2026-08-26

The Capability Buyers Forget to Check
Component enquiries almost always specify the casting: alloy, tolerance, volume, finish. Very few ask the question that determines how the next three years actually go — who maintains the die, and how fast can they fix it?
A production die is a consumable asset under constant thermal attack. Cavities heat-check. Gate inserts erode. Core pins crack. Ejector systems wear. None of this is failure; it is the normal service life of tool steel cycling between 200°C and contact with 660°C aluminium.
What differs enormously between suppliers is the response. A foundry with no tool room sends your die out, waits, and quotes you the downtime. A supplier with in-house tool and die capability replaces the affected insert and resumes production — often without touching the rest of the die.
Our die casting services include a full tool room: die design, build, refurbishment, reverse engineering and insert-level repair, alongside casting in aluminium, zinc and magnesium, Cnc Machining, finishing and assembly.

Modern aluminium die casting workshop showing a row of cold chamber die casting machines with holding furnaces, orange automatic ladle arms, operator at control console and a slat conveyor carrying freshly cast aluminium components

Capabilities Summary

Capability	Specification
Clamp force	160 – 2,000 tons
Processes	Cold chamber · Hot chamber
Alloys	Aluminium · Zinc · Zinc-aluminium · Magnesium
Part weight	10 g – 30 kg
Cavity configuration	Single, multi-cavity and family tools
Tolerance, as-cast	±0.10 mm per 25 mm (NADCA)
Tolerance, machined	±0.02 mm
Minimum wall — aluminium	1.2 mm
Minimum wall — zinc	0.4 mm
Die life — aluminium	200,000 – 350,000 shots
Die life — zinc	500,000 – 1,000,000 shots
Tooling lead time	5 – 8 weeks (bridge tooling 3 – 5 weeks)
In-house tool room	Design · build · repair · retooling
Certification	ISO 9001:2015 · IATF 16949

Tool & Die: The Service That Protects Your Schedule

Tool and die workshop in a die casting factory showing an opened hardened steel die casting mould with runner channels and ejector pin holes, CNC sinker EDM machine and racks of numbered die inserts

Insert-Level Repair Instead of Full Replacement

When a gate washes out or a core pin cracks, the instinctive assumption is that the die is finished. It rarely is. Modern die construction uses replaceable inserts — the cavity block, gate insert and core pins are separate hardened components mounted in a die base that may still have 200,000 shots of life left.

Replacing a single insert costs a fraction of a new tool and takes days rather than weeks. Two conditions make it possible:

The die was designed with inserts from the start.
Monolithic cavities cannot be repaired this way. We build modular from the first tool.
The supplier has EDM and high-speed machining on site.
Sending the die out adds transit in both directions plus another queue.

Reverse Engineering for Legacy Tooling

Programmes inherit dies. A supplier exits the business, a product transfers, an original drawing disappears — and you hold a tool nobody has a model for.

Our three-step process rebuilds the data: 3D scan the cavity and existing parts to capture actual geometry, map it against measured castings to separate intended dimensions from accumulated wear, then model replacement inserts to the corrected geometry. The result is a tool that can be maintained rather than one that must be abandoned when it next fails.

This also matters for die cast metal parts where the original supplier optimised the gate over years of production. That process knowledge lives in the steel. Scanning it preserves it.

Simulation Before Steel

MAGMASOFT solidification analysis runs before any cavity is cut, predicting fill sequence, air entrapment zones and last-to-freeze regions. Each avoided cavity modification saves three to four weeks. A supplier running simulation only after a failed T1 trial is using it as a diagnostic tool, and charging you for the difference.

Casting Processes

Cold Chamber — Aluminium and Magnesium

The shot sleeve sits outside the melt. An automatic ladler transfers a metered charge each cycle, then a hydraulic plunger injects at 700–1,200 bar, filling the cavity in milliseconds.

The separation is mandatory, not preferred. Molten aluminium at 660°C chemically attacks submerged ferrous components, dissolving them within hours and driving iron content past the 0.9% limit most structural specifications allow.

Suits: housings, gear casings, transmission adaptors, valve covers, oil coolers, brackets.

Hot Chamber — Zinc and Zinc-Aluminium

The gooseneck injection system sits submerged directly in the zinc pot. Zinc's 385–400°C working temperature is gentle enough that submerged hardware survives, and removing the ladling step cuts several seconds per cycle.

Suits: small appliance components, instrumentation, gauging applications, thin-walled and intricate parts.

Alloy Selection

Alloy	Characteristics	Typical Use
A380 / ADC10	Best all-round castability, strength and machinability	Housings, gear casings, enclosures
A383 / ADC12	Higher fluidity than A380 for intricate geometry	Complex thin-wall parts
A360	Superior corrosion resistance, higher ductility	Marine and outdoor equipment
A413	Highest fluidity, excellent pressure tightness	Manifolds, oil coolers, hydraulic bodies

Zinc and Zinc-Aluminium

ZAMAK 3 / 5 / 7 — walls to 0.4 mm, plating-ready as-cast surface, exceptional tool life.

ZA-8 / ZA-12 / ZA-27 — higher aluminium content gives greater strength and hardness than standard ZAMAK, with ZA-27 approaching bronze bearing properties. Useful where a zinc part must carry more load than ZAMAK allows.

Magnesium

AZ91D / AM60B — lowest density at 1.8 g/cm³ with natural EMI shielding. AM60B offers better ductility and impact resistance than AZ91D, which matters for parts that must survive a drop test.

Two Points Raised Before Tooling

A380 does not anodise bright. Its 3–4% copper produces a mottled dark grey film rather than clean silver. Where bright anodised appearance is required, we specify A360 or A413 during design — changing alloy after tooling is cut may force gate and thermal re-engineering.

Wrought alloys cannot be cast. 6061 and 6063 carry only 0.4–0.8% silicon, giving poor fluidity and a wide freezing range that hot-tears in a steel die. A drawing calling for 6061-T6 needs CNC machining from billet or aluminum fabrication from extruded profile. We flag this at quotation rather than substituting A356 silently.

The "As-Cast" Question

A recurring request is a part usable as cast — no machining, leak-free at assembly. It is achievable, but only when three conditions are engineered together from the start.

Gate and overflow position must place the weld line away from the sealing face. Where two metal fronts meet, the join is metallurgically weaker and more likely to leak. Simulation locates that line before the die is cut.
Vacuum assist must be specified. Evacuating the cavity below 50 mbar before injection removes the air and lubricant vapour that would otherwise form leak paths, cutting gas porosity 60–80%.
The sealing face must be a cast surface with defined flatness, not an afterthought. As-cast flatness runs about 0.15 mm per 100 mm. If the seal design needs better than that, the face must be machined and the as-cast ambition abandoned.

Where all three align, the part ships without secondary machining and the cost saving is substantial. Where they do not, discovering it at T1 is expensive — which is why the question belongs in DFM.

Secondary Operations and Finishing

Die casting factory assembly area showing a technician installing threaded inserts into an aluminium die cast housing with finished components in as-cast, anodised, powder coated and machined finishes

Precision machining — bores, threaded ports, sealing faces and datums to ±0.02 mm. Threads are machined rather than cast, because cast threads rarely reach the surface finish required for reliable sealing.

Surface Finishing:

Process	Build	Primary Benefit
Shot / bead blasting	—	Uniform matte texture, deflashing
Chromate / chemical conversion	0.5–2 µm	Corrosion protection, 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
Wet paint	25–75 µm	Colour matching, touch-up capability
Electroless nickel	5–50 µm	Uniform hard corrosion-resistant layer

Two details that cause assembly failures:

Anodising insulates; chemical film conducts. If a die cast housing relies on a bolted joint for chassis ground or wall continuity for EMI shielding, a fully anodised part breaks that path. We mask grounding pads or treat them with chemical film only, recorded as a defined zone with a stated resistance limit.

Coating consumes clearance. Anodising grows roughly half into the substrate and half outward, so 25 µm hard anodise reduces a bore by around 25 µm. Powder coat at 60–120 µm is more severe and builds unevenly on edges. State on the drawing whether dimensions apply before or after coating.

Assembly and outsourcing management — threaded inserts, press-fit bearings, seals, sub-assembly build and functional test. Where a programme needs operations outside our scope, we manage those sub-suppliers directly rather than handing you a coordination problem.

Metal fabrication — laser cutting, CNC press brake forming, TIG and MIG welding. Many products are best built as hybrids: a cast body carrying the complex sealed geometry with custom metal fabrication brackets attached, which often removes two side actions from the die. Because both routes run in-house, tolerance stack-up is engineered by one team rather than disputed between two suppliers. For low-volume structural fabrication — frames, chassis, panels — no tooling is required and parts ship in one to three weeks.

Quality Assurance

Certification: ISO 9001:2015 · IATF 16949. PPAP Level 3 submissions including FMEA, control plan, MSA and capability study. Military and industry-specific specifications supported on request.

Five inspection gates:

Incoming material

— optical emission spectrometry verifies alloy chemistry per heat before charging, cross-checked against the mill certificate. Metallurgists review both chemical and physical analysis.

First article

— full-dimension FAI with actual measured values and the instrument identified per feature.

In-process

— shot velocity, intensification pressure and fill time captured every cycle against the qualified window, with automatic quarantine of out-of-window parts. SPC on critical dimensions targeting Cpk ≥ 1.33.

Final

— CMM verification against GD&T, X-ray to ASTM E505 with drawing zone map, mechanical testing, and leak testing at rated pressure where specified.

Outgoing

— document package: material certificate per heat, dimensional report with actual values, treatment records, NDT results, and packing list with lot traceability to heat number and production date.

Porosity control. Gas porosity — rounded dispersed pores from entrained air and lubricant vapour — is controlled by vacuum assist. Shrinkage porosity — irregular voids where gates freeze before heavy sections solidify — is controlled by local squeeze pins driven into the semi-solid section, or eliminated at DFM by coring out isolated thermal mass. Pressure-tight parts require both.

Is Die Casting Right for Your Part?

Die casting is not the answer to every metal component, and recommending it when it does not fit costs both sides.

Die casting suits: volumes above roughly 5,000 pieces per year, walls under 4 mm, complex geometry with integrated features, thermal management requirements, and parts needing repeatable dimensional accuracy.

Consider alternatives when:

Situation	Better Route
Under 200 units, tight tolerances	CNC machining from billet
Under 500 units, thick walls	Sand casting
T6 mechanical properties required	Gravity or low-pressure casting in A356
Very large or heavy parts	Sand casting
Flat and bent stock geometry	Custom fabrication
Simple high-volume flat parts	Metal stamping
Maximum strength, forged grain flow	Forging

The T6 exclusion deserves explanation because it surprises most engineers. Conventional high-pressure casting fills at 30–60 m/s, entraining gas as dispersed high-pressure pores. A T6 solution soak at 500–540°C expands that gas while the aluminium softens, lifting the skin into unrepairable blisters. HPDC parts are supplied as-cast or T5 aged. If your drawing specifies T6, either the process changes or the requirement does.

Industries Served

Automotive and heavy vehicle

Electronics and power systems

Industrial equipment and automation

Lighting

Appliance and consumer hardware

Medical and defence

Automotive and heavy vehicle — diesel engine covers, gear casings, transmission adaptors, valve covers, oil coolers, intakes, rocker lever housings, filter brackets.

Electronics and power systems — housings, heat sinks, connectors. Thermal management and EMI shielding both depend on wall continuity and coating choice.

Industrial equipment and automation — gear housings, robotics brackets, machinery components produced at scale with consistent cycle performance.

Lighting — LED street light and high-bay housings, where fin geometry and coating determine thermal performance.

Appliance and consumer hardware — small appliance components, instrumentation, gauging applications, and decorative hardware where zinc casting delivers 0.4 mm walls and a plating-ready surface.

Medical and defence — instrument housings and enclosures with full material traceability and specification compliance.

Frequently Asked Questions

Q1: What happens when a production die wears out?

Rarely does the whole die fail. Modern dies are built with replaceable inserts — cavity blocks, gate inserts and core pins mounted in a die base that often has substantial life remaining. When a gate washes out or a pin cracks, we replace that insert in days at a fraction of new-tool cost. This requires two things: the die must have been designed modular from the start, and the supplier must have EDM and high-speed machining on site. Sending a die out for repair adds transit both ways plus another queue.

Q2: Can you work with tooling from another supplier or with no original drawings?

Yes, through reverse engineering. We 3D scan the cavity and existing castings to capture actual geometry, map that against measured parts to separate intended dimensions from accumulated wear, then model replacement inserts to the corrected geometry. This is particularly valuable for legacy oem casting programmes where the original supplier has exited or the drawings are lost, and it preserves gate optimisation that took years of production to develop.

Q3: Can a die cast part be used as-cast without machining?

Yes, when three conditions are engineered together. Gate and overflow position must place the weld line away from any sealing face, since that join is metallurgically weaker and more likely to leak. Vacuum assist must be specified to remove air and lubricant vapour that form leak paths. And the sealing face must be designed around as-cast flatness of roughly 0.15 mm per 100 mm. If the seal needs better than that, machining is required. These decisions belong in DFM, not at T1.

Q4: What tolerances can die casting achieve?

As-cast aluminium holds 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 reaches ±0.02 mm. Treat claims of ±0.01 mm as a casting tolerance with caution — that belongs to secondary machining. Apply tight tolerances only to critical-to-function features; a drawing carrying ±0.05 mm everywhere forces machining of every surface and can double piece price.

Q5: Should I choose aluminium, zinc or magnesium?

Aluminium at 2.7 g/cm³ suits structural parts, thermal management and service above 100°C. Zinc casting suits small detailed parts under roughly 500 g requiring walls below 1 mm or decorative plating, with far longer tool life. Where a zinc part needs more strength than ZAMAK provides, ZA-8 through ZA-27 offer progressively higher strength and hardness. Magnesium at 1.8 g/cm³ is lightest with natural EMI shielding, with AM60B preferred over AZ91D where impact resistance matters.

Q6: When is die casting the wrong process?

Below roughly 200 units with tight tolerances, CNC machining from billet avoids tooling entirely. Below 500 units with thick walls, sand casting is more economical. Where T6 properties are mandatory, conventional high-pressure casting cannot deliver them and gravity or low-pressure casting in A356 is required. Very large or heavy parts suit sand casting. Geometry buildable from flat and bent stock suits fabrication, and simple high-volume flat parts often suit stamping.

Q7: Do you manage secondary operations you do not perform yourself?

Yes. CNC machining, finishing, insert installation, leak testig and assembly run in-house under the same quality system. Where a programme requires an operation outside our scope, we manage that sub-supplier directly — handling the specification, the quality requirement and the schedule — rather than handing you a coordination problem across multiple vendors.