Investment Casting UK

What is Investment Casting?

Investment Casting, also known as Lost Wax Casting, is an industrial metal-forming technique that uses wax moulds to create complex metal structures.

Investment casting is a technique that has been used for thousands of years, with its earliest recorded use dating back to 2500 BC used to create idols, ornaments and jewellery. In its earliest uses, natural beeswax was used for the patterns and clay was used for the moulds. These days, we use master die wax to create an infinite range of designs.

That wax is then coated in a thick layer of ceramic shell castings to create the mould. Once the precision casting has dried and solidified the wax-casting is placed in a furnace where the wax melts out of the cast leaving just the mould. Whilst the mould is still hot liquid metal is poured into the cast, allowing it to go into the small grooves and corners., where it is then cooled down and the cast is removed.

Examples of Sylatech Lost Wax Castings

Lost Wax Casting

At Sylatech, our unique block moulding version of the lost-wax investment casting method affords customers a process capable of producing thin walls and lightweight components. Working exclusively in the casting of non-ferrous metals, our specialist process delivers small castings with a ceramic shell wall thickness as fine as 0.2 mm, and more typically 1-3 mm. Our rapid prototyping capability affords engineers a fast route to test their prototype designs in metal, within a few days.

Sylatech’s in-house tooling capability is integral for the production of tools, which are used in the creation of wax patterns. To facilitate the casting process, the gating system is incorporated within the design of the tool.

The plaster-based refractory materials used within Sylatech’s lost-wax casting manufacturing processes cannot sustain a high temperature when the molten metal is poured. This limits the process to the casting of non-ferrous metals only. This is unlike ceramic mould materials formed from a ceramic slurry which are used when creating stainless steel castings.

Whilst metal casting is commonly known as a process for producing near-net-shape components, through Sylatech’s additional in-house CNC machining capability, we can ensure that all castings have exacting dimensional accuracy. Sylatech’s manufacturing method affords greater benefits to other investment casting processes, particularly pressure die casting and sand casting, which cannot compete with the surface finishes, lightweight and fine tolerances achieved by our plaster-based process.

Sylatech is certified to AS9100D and to Nadcap for Welding.

Lost Wax Casting Process

Sylatech’s foundry casting process achieves excellence in the production of copper and aluminium alloy lost wax investment castings.

The lost wax casting process provides a fast and cost-effective method for both small batches and large quantities of up to 150,000 per year. Parts with complex internal and external detail, superior finishes and thin wall capabilities can be produced, without the need for machining from solid.

Our process is capable of producing non-ferrous foundry castings with a wall thickness as fine as 0.2 mm, and more typically 1-3 mm. Our rapid prototyping capability affords engineers a fast route to test their prototype designs in metal within a few days.

Our specialist lost wax investment casting process affords us the ability to take a customer’s concept and achieve reality in a fast and cost-effective manner. By combining our non-ferrous investment casting technology with best practice CNC machining, Sylatech can overcome many of the constraints placed on engineering design whilst delivering the highest quality.

Metal Casting Company

Sylatech is one of the largest Metal Casting Companies in the UK, manufacturing a wide range of bespoke metal components for a broad range of companies across the globe. We are supported by a heritage of 57 years of delivering precision custom metal castings.

We are trusted by our partners to produce high-quality systems and components matching their exact designs.

Global Sourcing

In response to customer demands to supply alternative alloys, Sylatech has developed relationships with a number of other suppliers globally.

Where projects require components from other suppliers, we are able to manage this process for you and aim to be a single source for all of our customer’s precision components.

We take full responsibility for ensuring the product is to the correct specification and the correct quality. We also actively manage all customs and shipping on behalf of our customers.

Examples of global sourcing projects that we have undertaken for our customers include:

Sizes and Tolerances

Sizing and Tolerances depend on the geometry of each part, but the following tolerances are suggested as a guide to designers.

Lengths including hole diameters held to:

Wall Sections

Constant section thin walls are preferred but large changes in the section can be accommodated through critical analysis of the component design and special tooling design features.

Special Features

Integrated Labelling

It is possible to include many types of permanent product identification which can eliminate the further need for labelling. Logos and text may be produced with the minimum cost if the design ensures that detail is in the line of the draw of the wax from its die.

Ideally, cast labels should use raised lettering on the casting face (engraved into the wax tool). Where such information must be below a functional surface, it can be sited on a pad sunk into the cast face.

Surface Finishes

As Cast

“As cast” – parts removed directly from the mould have a surface finish equal to or better than 0.8 micrometres (32 micro inches); this finish may show variable colour.

Chip Rumbling

Removes any sharp edges left after finishing, leaving a surface suitable for most subsequent “finishing” processes.

Shot Blasting

Using stainless steel shot is generally suitable for brass components and gives a slightly polished surface.

Glass Bead Blasting

Produces a more highly polished surface finish and is most suitable for aluminium parts.

Special Surface Effects

Such as textures and knurling can be incorporated within the Sylatech casting process.

Automatic Grit Blasting

Gives a uniform matt finish, suitable for most subsequent finishing operations.

Applied Surface Treatments

The following treatments can be applied:

Alocrom1200/1000 / Chromate Conversion

Surtec 650 Roche complaint processes provide corrosion resistance to aluminium parts whilst providing an electrically conductive surface.

Anodising

Protective purposes can be carried out on aluminium alloy castings but cast alloys do not readily accept decorative anodised finishes due to the silicon content.

Plating

Can be applied to most alloys.

Hipping (Hot Isostatic Pressing)

Is used to improve the mechanical properties of aluminium castings by sealing internal voids.

Impregnation

Can be carried out on “as cast” or machined parts where pressure tightness is essential.

Paint/Powder Coating

For protection or visual purposes.

Heat Treatment

Various heat treatments can be applied to harden components. This is carried out generally to aid subsequent machining and enhance component stability. Suffixes to the material grade are used to denote the heat treatment carried out: UK and equivalent USA and EN suffixes are shown below:

TreatmentsUKUSAENAs cast/manufacturedMFFSolution heat-treated and artificially age hardenedTB7T4T4Artificially age hardenedTET5T5Solution heat-treated and artificially age hardenedTFT6T6