Die Casting in Australia: How It Compares to CNC Machining and Other Casting Methods
Die casting gives the lowest price per part for repeat production of aluminium and zinc components, but it needs a die first. Compare it with the alternatives, see where it pays off, and learn how to source it.
The short answer
Choose the process by quantity and material:
- Die casting for repeat production of aluminium or zinc parts, where the die cost is spread across many parts.
- CNC machining for prototypes, small batches and the tightest tolerances, with no tooling cost.
- Investment casting for complex steel or stainless parts at medium volumes.
- Sand casting for large, heavy parts in small numbers where finish matters less.
Die casting vs CNC machining, investment casting and sand casting
How the four most common ways to make a metal part compare on cost, detail and speed.
Swipe the table sideways to see every process →
| Comparison | Die castingThis page | CNC machining | Investment casting | Sand casting |
|---|---|---|---|---|
| Best for | Repeat production of aluminium and zinc parts | Prototypes, small batches and the tightest tolerances | Complex steel parts at medium volumes | Large, heavy parts in small numbers |
| Materials | Aluminium and zinc alloys | Almost any metal or engineering plastic | Carbon, alloy and stainless steels | Iron, steel, aluminium and bronze |
| Tooling cost | High: hardened steel die | None | Medium: wax pattern tool | Low: pattern |
| Cost per part at volume | Lowest | Highest | Medium | Medium |
| Detail and thin walls | Excellent | Excellent, but cost rises with complexity | Excellent | Limited |
| Surface finish | Smooth as cast | Smooth, machined | Smooth as cast | Rough, usually machined |
| Tolerances | Good as cast; critical features machined | Tightest | Good as cast; machined where needed | Loosest |
| Time to first parts | Longest, die build first | Shortest | Medium | Short to medium |
Ratings are general guidance. Your manufacturing advisor confirms the best process for your drawing.
When does die casting become the cheapest option?
Drag the slider to change the order quantity and see which process gives the lowest cost per part.
Illustrative example for a mid-sized metal part, not real prices. Crossover points depend on your part's size, material and complexity, so your quote shows unit prices at several quantities.
Aluminium vs zinc die casting
Both are die cast, but they suit different parts.
Aluminium die casting
Light, strong and corrosion resistant. The usual choice for housings, enclosures and structural brackets.
- Alloys such as ADC12 and A380
- Automotive and 4WD housings, brackets and covers
- Powder coat or anodise for finish
Zinc die casting
Fills fine detail and very thin walls, plates beautifully, and its dies last longer.
- Zamak alloys
- Small fittings, hardware and decorative parts
- Chrome, nickel or other plated finishes
Relative ratings out of 5, for comparison between the two alloys only.
Where to get die casting for an Australian business
Once you have chosen die casting, the next decision is who makes the die and the parts.
Swipe the table sideways to see every option →
| Comparison | Local Australian foundry | Overseas marketplace | RTech factory-direct |
|---|---|---|---|
| Who makes your part | The local foundry | Whichever supplier takes the job | Our own factory |
| Die price | Typically the highest | Varies by supplier, plus platform margin | Factory-direct, no markup |
| Price per part | Typically higher | Lower, plus platform margin | Factory-direct, no markup |
| Freight, customs and duty | Not needed | Often quoted separately | Included, one price to your door |
| Lead time | Depends on local capacity | Varies by supplier | 4–8 weeks to your door |
| Inspection report | Varies by foundry | Varies by supplier | With every order |
| Die ownership | Usually yours | Varies by supplier | Yours, stored for reruns |
| Face-to-face visits | Easiest | Not usually possible | Dedicated advisor in Sydney |
General comparison. Individual foundries and suppliers vary.
From drawing to die-cast part
One price agreed up front, and one manufacturing advisor the whole way.
Send your drawing
CAD or PDF drawing, with quantity, alloy and finish.
Die design review
Draft, wall thickness and gating checked before steel is cut. Price and lead time within 48 hours.
Die build and samples
Your die is built in our toolroom and first-article samples are measured against your drawing.
Production and machining
Parts are cast, machined on critical features and finished as specified.
Delivered duty paid
Shipped, cleared and delivered to your door with the inspection report and material certificates.
Die casting questions
Is die casting cheaper than CNC machining?
Per part, yes, once your quantity is high enough to cover the cost of the die. For prototypes and small batches, CNC machining is usually cheaper because there is no tooling to pay for. Your quote shows the unit price at several quantities, so you can see where die casting starts to pay off.
How many parts do I need for die casting to make sense?
It depends on the size and complexity of the part, but die casting usually makes sense for repeat production runs in the hundreds or more. Lower quantities are often better CNC machined or investment cast.
Should I choose aluminium or zinc die casting?
Aluminium suits lighter, larger parts such as housings and structural brackets. Zinc suits smaller parts with fine detail, very thin walls or a plated finish, and zinc dies last longer. Your manufacturing advisor will recommend an alloy for your part.
Who owns the die-casting die?
You do. When you pay for a die, it belongs to you. We store and maintain it for your repeat runs, and release it to you on request.
How long does die casting take?
Most orders arrive 4–8 weeks after you approve the quote. A new die adds die build and sample approval before production, and your quote gives a confirmed delivery date. Repeat orders from an existing die are faster.
Can die-cast parts be machined and finished?
Yes. Critical faces, bores and threads are CNC machined after casting in the same factory, typically to ±0.05 mm, then finished with powder coat, anodising or plating as your drawing specifies.
Do I pay customs duty on die-cast parts?
No. Prices are delivered duty paid: freight, customs clearance and import duty are included in one price, so there is no separate bill when the parts arrive.
Related guides
Ready to price your die-cast part?
Send your drawing and we will come back with one price delivered duty paid, a lead time and any design notes.