High pressure die casting, machined to print.

High pressure die casting (HPDC) is the process for high-volume aluminium and zinc parts that need tight tolerances, thin walls and a clean as-cast finish straight out of the tool. Solstice sources HPDC through audited partner foundries in the Far East, CNC machines each part to your drawing and manages quoting, tooling, quality and logistics from the UK.

When to choose it

When HPDC is the right choice

Volume

Best suited to series production, where tooling cost is spread across thousands of parts.

Thin walls and fine detail

Molten metal injected under high pressure fills thin sections and complex features that gravity processes can't.

Surface finish

A good as-cast surface, so less finishing work before coating or plating.

Repeatability

Steel tooling holds part-to-part consistency across long runs.

HPDC at a glance

Materials

Aluminium, zinc

Part weight

< 50 g – 15 kg

Tooling

New build or existing tool transfer

Volumes

Prototype through to series production

Drawings

2D/3D CAD, or a physical sample part

Delivered

CNC machined and finished to print, on a UK invoice

Limits

When it isn't

HPDC parts can contain trapped gas porosity, so they are generally not heat treated or welded. Where strength or pressure-tightness matters most, gravity die casting or low pressure die casting may suit better. We'll recommend the right process at quote stage.

High pressure die cast aluminium housing, CNC machined bore and mounting faces

Process

Cast, then machined

Every HPDC part that needs it is CNC milled, turned, drilled and tapped to your finished dimensions as part of the same production run. Bores are machined and threaded, mounting faces finished flat and ports opened to size, so parts arrive ready to fit, not just ready to cast. Finishing (shot blasting, powder coating, plating), leak testing and sub-assembly can be coordinated in the same order.

Materials & parts

Materials and typical parts

Aluminium

Aluminium alloys, e.g. LM24 / A380 / ADC12 equivalents.

Zinc

Zinc (Zamak 3 and Zamak 5). See zinc die casting.

Typical parts

Housings, enclosures, covers, brackets, heat sinks and gearbox or pump bodies.

FAQ

Common questions

Can you take over an existing HPDC tool?

Yes. We can transfer existing tooling to a partner foundry as well as build new tools.

Can HPDC parts be pressure tight?

With the right design, impregnation and leak testing, many can. We'll advise at quote stage.

What do I need to get a quote?

A 2D or 3D drawing, annual volume and finish requirements. A sample part works too.