Vacuum casting

Vacuum casting is a manufacturing process used to make small batches of parts. It starts with a master model (like a prototype) to create a silicone mold. Liquid material, usually plastic, is poured into the mold under a vacuum to remove air bubbles and ensure a smooth, detailed part.  It's commonly used in industries like automotive, electronics, and medical devices to test designs or make small amounts of final products.

 Process 

 Master Model: Start with a high-quality model, often made by 3D printing or CNC machining.
 Silicone Mold: Cover the master model with liquid silicone to create a mold, then let it harden.
 Remove the Model: Cut the silicone to take out the master model, leaving a cavity shaped like the part.
 Pour the Material: Pour liquid plastic or resin into the mold under vacuum to remove air bubbles.
 Cure the Part: Let the material harden, then remove the finished part from the mold.

 Materials 

Vacuum casting is mostly used with polyurethane resins, which can look and feel like rubber or strong plastic. Some resins can also copy the properties of materials like ABS or PP. Sometimes, colored dyes are added to the resin to match the look of the final product.

 Advantages 

 Low cost for small quantities.
 Good surface finish and fine details.
 Fast production time (usually a few days).
 Useful for making prototypes or testing parts before mass production.

 Limitations 

 Not suitable for very large parts.
 The silicone mold wears out after 20–25 uses.
 Less strong than injection molded parts.
 Limited material options compared to other processes.

 Common Uses 

Vacuum casting is often used in:
 Prototyping: to test product shapes, designs, or functions.
 Pre-production: samples: to show customers or test in the field.
 Bridge production: small batches before switching to mass production.
 Design and fit checks: when checking how parts will connect or fit into a product.

References

Category:Manufacturing