Why is Vacuum casting preferred to Injection molding

by David Woolf

You must have heard of vacuum casting if you have been in the manufacturing industry. Vacuum casting among other prototyping processes such as rapid injection mold tooling is a vital process in the formation of designs for prototyping services or the production of the end product. Vacuum prototyping is essential and of advantage to you especially if you are a dealer of cases, covers and production of flexible and rigid parts of a design. This process is inevitable if you need to proof your concepts, test the functionality of your design and even used it for the display of demos before actual production or purchase of the ideal product.

Why is Vacuum casting preferred to Injection molding

Do you know the difference between the performances of these two processes? Injection molding uses a screw to push through the liquid material into a mold.

Do your products have undercuts or do they have fine details, then vacuum casting is your best prototyping service.

Vacuum Casting

Let us look at how the vacuum casting process is done.

Master making stage; this is the first stage in the vacuum casting process. In this stage, there is something called matter, which are the 3D solids made in the CAD designs. These solids are either made by CNC machining or with 3D printing processes. The master is made under 40 degrees Celsius.

Mould making; This is the second phase where the mould is made from liquid silicone. You are required to fill the casting box with the silicone liquid halfway. The casting box is to be heated up to the curing state of the silicone then allowed to cool down for 16 hours. Heat the remaining silicone liquid and fill it on the casting box whereby upon drying the mould is cut and the master is removed.

Parts Making;

Proceed to pour the casting resin into the empty cavity to be able to create a highly accurate copy of the original. Overmolding is also possible with more than two materials.

Advantages of Vacuum casting

Cheap; Injection tooling is very expensive compared to vacuum casting. The production process should be cost-optimized in this case, vacuum casting is the most cost-efficient process you should opt to consider.

Ability to create large parts

Vacuum casting can produce parts of diverse sizes. This will depend on the equipment being used. The ability to create large parts puts vacuum casting at a great preference level than other prototyping services.


This is a very adorable advantage for vacuum casting. The silicone can be able to be reused close to 20 times without replacing it. Is that not great, it sounds economical and reliable. You can save costs and have a great chance to produce as many profiles as possible.

Great surface finishing

Do you want well finished and good-looking products? You need to consider the vacuum casting process. Vacuum casting eliminates all the air bubbles leaving the product to shine. The physical appearance of your product matter a lot to the market therefore you should prioritize where you get the best finishing ever.

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