Home » Prototyping » Vacuum Casting

Vacuum Casting - Urethane casting

Leshine is fully capable of handling your vacuum casting and silicone molding needs. With years of expertise in the field, we can fabricate your parts to the highest standard and with fast turnarounds.

Vacuum casting is a great way to make rigid or flexible parts, and is ideal for prototypes, engineering testing, concept proofing and display demos. These parts can be made from hundreds of casting polymers.

Contact us today for more information.

Advantages of Vacuum Casting

1. Fast turnaround

Leshine can provide up to 20 parts in 15 days or less, depending on part specification and volume.

2. Affordability

Silicone molds are less expensive than the tooling used for injection molding, resulting in low prices.

3. Capable of producing large parts

Depending on the type of equipment used, vacuum casting can to create very large parts.

4. Superior surface finish to injection molding

The vacuum process removes air bubbles and allows the material to capture fine details.

5. Color options

Coloring pigments can be added to the resin for a variety of color options.

6. Repeatability

Silicone molds can be used around 20 times before they need replacing.

Common Vacuum Casting Applications

  • Visual prototypes
  • Concept proofs
  • Cases and covers
  • Low-volume production
  • Market testing
  • Investor pitches
  • Trade shows

What is Vacuum Casting?

Vacuum casting is a manufacturing technology that uses a vacuum to draw liquid material into a mold. It differs significantly from injection molding, which pushes liquid material into a mold using a screw. 
The process of vacuum casting offers significant advantages, and is particularly useful for parts that have undercuts or fine details. 
The process starts with a master model, which Leshine creates using one of its CNC machining centers — though 3D printing can also be used. This master model is then immersed in liquid silicone, which is cured and becomes the mold. 
Once it has been cut and the master model removed, the silicone mold can be put to use. This stage involves pouring casting resin into the mold, as the vacuum removes bubbles and air pockets to ensure a smooth finish. 
The resin part is then cured and removed from the silicone mold, which can be reused around 20 times. 
Each resin part is an exact copy of the original master model.

Vacuum Casting Process

Step 1:Master building
    Masters are 3D solids of your CAD designs. They are usually made by CNC machining or with 3D Printing.
    Making Master in 40° temperature. After finish and inspect the masters, we will move to silicone mold making.
Step 2: Mold making
    Casting molds are made from liquid silicone. Half-Fill the  casting box with liquid silicone, Heat the casting box  until silicone
    is fully cured and then allowed to cure in an oven for 16 hours. Fill with extra silicone  liquid which is also  heated & cured.
    Once dried, the mold is cut open and the master removed.
Step 3: Make the parts
    Poured the  casting resins into the empty cavity to create a highly accurate copy of the original. It’s even possible to
    overmold with two or more materials. Silicone molds are typically good for 20 or so copies of the master pattern.

Vacuum Casting Technical Specifications

Typical lead time
    Up to 20 parts in 15 days or less, depends on the part specification and volumes.
    ± 0.3% (with lower limit on ± 0.3 mm on dimensions smaller than 100 mm)
Minimum wall thickness
    To ensure that the mold is filled properly, a wall thickness of at least 0.75 mm is necessary.
    For best results, we recommend a wall thickness of at least 1.5 mm
Maximum part dimensions
    The size of the mold is limited by the dimensions of the vacuum chamber (1900 x 900 x 750 mm)
    and by the volume of the product (maximum volume: 10 liters)
Typical quantities
    Up to 25 copies per mold (depending on the mold’s complexity and the casting materials)
Color & Finishing
    Pigment is added to the liquid polyurethane prior to casting, custom painting and texture. 

Start Your Project With A Free Quote

Contact Us



Add:308 Excellence Times Building,CentralRoad,ShaJing,

Copyright Leshine Technology Co.,Ltd.    ICP :17013688号                                Designed By: hefoweb

Send Us A Message