Vacuum Casting

Vacuum casting

Vacuum casting is the process of simulating injection-moulded parts both visually and functionally. This process takes a painted prototype to the next level of realism and can save time and cost on injection moulding; parts from master to first production in two days can be achieved. Your requirement for CAD time can be greatly reduced as the silicone tooling used is very forgiving and allows negative draft as well as some undercut details.

Vacuum casting is typically used to produce small batches of highly accurate prototype parts. We’re constantly researching materials and processes to make ever more accurate products, narrowing the gap between prototypes and injection-moulded parts. Our experience with casting resins and advanced polymers has meant that we have vacuum cast parts with a tolerance of +/– 0.05mm; we believe that this is the highest tolerance achieved in vacuum casting.

Our experience with casting resins and advanced polymers allows us to create working prototypes which can mimic almost any industrial method of production. We use various polyurethane resin systems for vacuum casting, creating highly realistic parts in small volumes. Our developments in this sector secured us as market leaders.

The process can replicates gloss and texture level, patterns, dimensions and profiles of the designed part. These details are replicated across multiple parts from the single tool. Parts also come from the tool self-coloured without the need for post painting. Vacuum casting at Complete Fabrications produces high quality parts for working assemblies.

We have resins that simulate most thermoset plastics/elastomers and also Roche compliant, fire rated materials and are FDA approved.


The process starts with a master, normally created via a 3D print which is hand finished by our model makers replicating intended final production finishes. From this master stage, a silicone tool is manufactured. The tool will then create a number of castings, in the region of 15 to 30 off parts per tool depending on resin choice and complexity of part. These silicone tools are processed under vacuum in the ‘vacuum casting machine’. Following a short period of time with the tools in an oven, the parts are ready to de-mould and our team will fettle the unwanted tooling details from the parts.

If you would like to find out more about our Vacuum casting services, call us on 01223 836837 or email

Vacuum casting Case Studies

  • I Dration water bottle

    I Dration water bottle

    The challenge was to make a working water tight drinking bottle that would have batteries and LED lights in the base

    read more
  • Vacuum casting

    Small Component

    We were challenged by our client to vacuum cast a very small component with very tight tolerances

    read more