Vacuum Casting VS Injection Molding

Last Updated on September 1, 2022 by Leizi

Both vacuum casting and injection molding are popular methods to create plastic parts. There are a few questions we often get asked as below. You will know more about them after reading our blog within minutes.

Vacuum Casting VS Injection Molding

Is vacuum forming cheaper than injection molding?

It depends on your project. Vacuum casting, also called vacuum forming, is characterized by forming the plastic molds within hours. At the same time, it takes more than one month to create injection molds. Therefore, if you get any low-volume prototyping project to do, vacuum forming will be more economical than injection molding. If you want to make high-volume plastic parts, vacuum forming will be much more expensive and time-consuming.

What are the advantages of vacuum casting?

Vacuum casting has been a preferred method for low-volume prototyping. It gets multiple advantages for your plastic fabrication project.

  1. Economical.Vacuum casting creates plastic parts by plastic mold. The cost of the mold is much cheaper than metal mold.
  2. Rapid Prototyping. The silicone mold can be made within hours.
  3. High-quality. The quality of vacuum casting prototypes is fine with well surface finish.

What are the limitations of vacuum casting?

There are some limitations of vacuum casting that you need to pay attention to.
1. The tolerance is not tight. The silicone mold is easy to shrink. The shrinkage is around 2%, which means that the tolerance of the finished plastic parts is not that tight. If your project requires highly on tolerance, vacuum casting is not an ideal option.

2. Only suitable for low-volume production. Because the lifespanof plastic mold is short because an individual silicone mold can only be used for 20 times. After being used 30+ times, the silicone mold will be deformed, which will affect the accuracy of the parts.

3. Extra assembly and simple design. It takes more time and energy to assembly the parts. Besides, the silicone mold can only be applied to create the plastic parts with comparatively simple design.

4. Continuous Flaws. If there is a problem on silicone molds, it will lead to inaccuracy of the parts. At the same time, if the master piece is not accurate, it will greatly affect the tolerance.

5. Limit to plastics. The material range for vacuum casting is only plastic. As for metal, it needs much higher temperature to be melt and formed. It will damage the silicone mold greatly.



Scroll to Top

Get a Quick Quote!