Vacuum casting and injection moulding both are widely used processes in the world of prototyping. Both vacuum casting and injection moulding have their advantages. Businesses often find it confusing to choose between the two processes because both processes have certain similarities.
Although it is always better to consult experts who will give you customised advice yet you can also decide for yourself. To make the best decision you should understand both processes first.
Meaning of injection moulding
Injection moulding is very commonly used in manufacturing processes. This process involves the injection of molten material into the mole. This process is used to manufacture parts in bulk. This process is very common for consumer and healthcare products.
The process of injection moulding includes heating and then mixing of materials. Once the material is melted it is poured into moulds. The mixture takes the form of the mould once it is cooled. This process is repeated multiple times to make similar products.
Apart from large scale production, vacuum injection molding is also widely used for manufacturing prototypes of parts. But, it is not a cost-efficient process for small scale production.
Meaning of vacuum casting
Although injection moulding is more popular than vacuum casting, it is a good alternative for small scale production.
A master model is dipped into the liquid silicon. The silicon is then removed from the mould. This silicon which has now taken the form of the master mould can be used as a mould. A vacuum is used to remove any air pockets or air bubbles to give the mould a smooth finish. The silicon mould can be easily used about 20 times which is perfect for small scale production.
Cases wherein vacuum casting is more suitable than injection moulding
Businesses generally prefer injection moulding over vacuum casting because of its popularity. However, in some situations, it is more suitable and profitable to use vacuum casting instead of injection moulding.
For large scale production where the manufacturer has to build hundreds and thousands of products injection moulding is the way to go. Although the cost of injection moulding is very high the per-unit cost comes out to be relatively low.
But not everyone needs to go for large scale production. When the quantity to be manufactured is small then vacuum moulding is a better and more cost-efficient method. The cost of setting up vacuum moulding is much lower than injection moulding making it perfect for small scale production.
If you are dealing with the manufacturing of more complex components then injection moulding would be a better option. Injection moulding is a better option for building detailed components. However, everyone doesn’t deal with the manufacturing of complex parts. For manufacturers who deal with the production of simple products with little details then vacuum casting is a better option. Apart from being relatively cheap as compared to injection moulding, vacuum casting also gives a smooth finish to the products because of its smooth silicone moulds. Products made via vacuum moulding look better and have a finished look.
Iteration and speed
There are numerous advantages of using vacuum casting instead of injection moulding. If you have to make changes in the design of the product, with vacuum casting you will be able to do so at any production stage. However, it will cost you a lot if you want to make even a slight change in the design of the product with injection moulding.
It means that it is better to choose vacuum casting during the initial stages of development. Businesses generally make prototypes via vacuum casting first and then they remake or rework it for injection moulding.
In addition, vacuum casting is a much faster process than injection moulding. Therefore if you have a time-sensitive project then you might want to go with vacuum casting rather than injection moulding. However, it is important to mention that injection moulding would be faster for large scale production.
It is important to note that some prototypes have to manufacture ultimately using injection moulding. However, it might be fruitful to make the prototypes using vacuum casting the end product should be manufactured using injection moulding. In a nutshell, the process you choose depends on the type of production and the material and type of the product