Choosing the Right Tooling: When Aluminum Outshines Steel

0:00–0:06 | Introduction

Narrator:
Hello everyone, and welcome to today's video.
We're going to dive into aluminum mould tooling for injection moulding.
Let's get started.

0:06–0:36 | The Initial Choice

Picture a part’s journey through injection moulding.
At the start, you must decide: aluminum or steel tooling.

This choice mainly comes down to quantity demands.
If you're producing over a million parts, steel tooling is your go-to — but heads up, it’s a big investment.

If your part volumes don’t stretch into the millions, aluminum tooling might be your best bet.
It’s a fraction of the cost and offers great benefits.

It’s perfect for product developers who need to be nimble — bypassing the high-volume paradigm of large investments, long wait times, and inflexibility.

0:36–1:02 | Why and When to Choose Aluminum

Why is aluminum so great?
It’s all about machinability.

Aluminum is softer than steel, which means we can CNC machine it much faster for moulding.
Faster machining equals lower costs — that’s always a win.

Typically, aluminum moulds can handle about 10,000 parts as a rule of thumb, but often they can do more.

Keep in mind, mould life depends on the material type and geometry,
and you’ll likely need to replace an aluminum mould before you would a steel one.

1:02–1:11 | Ideal Scenarios for Aluminum Tooling

Aluminum tooling is ideal if:

• Your part volumes don’t stretch into the millions
• You need on-demand production parts within days
• You want to avoid risky tooling investments before your design is fully validated

1:13–2:18 | Pros of an Aluminum mould

Let’s break down some key benefits.

Aluminum moulds start around $1,500 and can be delivered in seven days or less.

Steel tooling, comparatively, has a longer lead time.

Aluminum tooling can produce at least 10,000 parts — often more.

At Protolabs, customers can choose either Prototyping or On-Demand Production for quantities and pricing that fit their needs.

Aluminum moulds can include:

• Single or multi-cavity tooling (1, 2, 4, or 8 cavities depending on size/complexity)
• Thermoplastic and thermoset materials identical to those used in high-volume production
• Over 100 materials available, including ABS, polycarbonate, polypropylene, liquid crystal polymer, and polyoxymethylene

Aluminum’s thermal conductivity allows for improved heat dissipation, reducing the need for complex cooling lines.

Additional cost savings include no maintenance fees, with mould damage covered over its lifetime.

2:21–3:25 | Design for Manufacturability: Aluminum moulds

Now, let’s talk about some design considerations.

Part Finish

• For critical aesthetics: SPI-A2 finish (diamond buff to 1–2 Ra)
• For non-cosmetic parts: PM-F0 as-machined surface — least expensive option

Draft

• Always add draft to aid part ejection.
• Prevents scraping, poor surface finish, bending, breaking, or warping.

Wall Thickness

• Follow material guidelines: typically 0.040–0.140 inches, applied consistently.

Radii

• Avoid sharp internal corners.
• Rounded edges reduce stress and improve structural integrity.
• Be generous with radii!

3:27–3:46 | Protolabs Tooling Options

Protolabs offers two service-level tooling options:

• Prototyping: Lower price point for limited quantities, with higher per-part cost.
• On-Demand Manufacturing: Longer mould life, ideal for multi-year, higher-volume production of end-use parts.

3:46–3:58 | Conclusion

And there you have it — a comprehensive look at aluminum vs. steel tooling in injection moulding.

If you have any questions, our team is always here to help.
Just give us a call or shoot us an email.

See you in the next video.