Vacuum casting

Introduction to Vacuum Casting

The 3D prototypes produced with this technology are the result of the creation of a silicone mold from a master model first produced in
Stereolithography
.

The silicone mold created from the master model is then filled with polyurethane resin, using a special vacuum casting machine.

Mould life can range from 6 to 30 parts, depending on the geometry of your parts and the polymer used.

This technology is therefore ideal for pre-series or low-volume production runs, which will have the same appearance and mechanical properties as the final product.

The printing dimensions of our largest machine enable us to produce parts up to 1300 x 750 x 800 mm.

Coulée sous vide MCP

The benefits of 3D printing technology

  • Possibility of using flexible, transparent or rigid materials, with mechanical and thermal characteristics similar to those of mass-produced materials;
  • Numerous finishes ;
  • Possibility of overmolding and adding inserts;
  • 3D part tinted in the mass;
  • Wide range of technical resins;
  • Soft/rigid bi-material moldings.

Vacuum casting materials and finishes

At Axis, we use the following materials:

  • Soft materials – Elastomer: from 25 to 95 Shores A ;
  • Rigid materials: close ABS, PA, PP, PC, PEHD.

Don’t hesitate to contact us for your specific needs, or consult our material sheets. Vacuum casting enables us to offer a highly flexible range of materials and colors to suit your needs.

Once your parts have been produced, we can offer you the following finishes:

  • Complete part deburring and assembly validation;
  • Realistic surface finish: gloss, satin, grained, frosted… ;
  • Paint finish ;
  • Mounting, adding inserts…

Lead times and part design advice

For the vacuum casting process, it takes 4 to 6 working days to create the mold, followed by production of 2 to 3 parts per working day. Please contact us to obtain the precise deadline for your project.

For the dimensions of your parts, we are able to comply with standard NFT 58-000 normal class.

La Coulée sous vide in pictures

How does it work?

There are several stages in the production of vacuum cast or duplicated parts:
  • Step 1: The first step is to create a master model in
    Stereolithography
    .

    • Once we have received your 3D file, we process it, program it and launch it into production, with or without shrinkage depending on the material ordered;
    • The master model goes into production using the Stereolithography process;
    • It is cooked to harden;
    • The 3D part is cleaned, sanded and blasted. The necessary finishing touches are provided by our prototypists, as the casting will have the same appearance as its master (graining, transparency, etc.);
    • Our moldmakers glue a marker along the parting line to make it easier to open the silicone mold.
  • Step 2: Making the mold
    • The Stereolithography master is levitated in a wooden box with the help of a sprue (a recycled feed sprue, which allows the material to circulate in the mold cavity) and vents (to evacuate air from the material);
    • Once the part has been installed, the silicone is poured into the box to take the impression;
    • When the silicone has hardened, our moulders open the wooden box along the parting line;
    • Once the silicone mold has been completely opened, the stereo master is carefully removed to avoid damaging the silicone.
  • Step 3: Making the duplication
    • The casting operator in charge of the project carefully closes the mold by hand, avoiding any gaps that might allow the polyurethane material to escape;
    • He installs it in his machine, prepares the two materials to be mixed separately and places them in the machine in the upper position;
    • The machine is closed and evacuated while mixing material A (isocyanate) and material B (polyol). The two materials are incorporated into each other under vacuum, then poured into the silicone mold by gravity;
    • When material emerges from all the vents created, the air is returned to the machine, and the filled mold is placed in a hot oven for several minutes while it hardens;
    • Once the material is hard, the casting operator demolds the part.

Our production facilities

  • 1 MCP 5/01: 400 x 400 x 400 mm

  • 1 MCP 4/01: 400 x 400 x 400 mm

  • 1 MCP 003: 560 x 600 x 600 mm

  • 2 MCP 4/04: 900 x 750 x 600 mm

  • 1 MCP 4/05: 1,300 x 750 x 800 mm

To find out more about our other additive manufacturing production resources, please visit our our machines page.

Need a quote or information on rapid prototyping?

Ask us for a quick quote or call us on +33 (0)5 55 06 17 17