Why is Vacuum Casting Preferred for Prototype Model Making?
Vacuum casting is a widely used technique for the production of plastic prototypes. Vacuum casting is not only more economical but also the ideal process for low to medium scale production of plastic prototypes. In essence, vacuum casting allows the users to create copies of a wide range of functional plastic parts. The whole process is relatively fast-paced as compared to other manufacturing processes and parts produced through vacuum casting are of high quality and better surface finish.Get more news about Vacuum Casting Rapid Prototypes,you can vist our website!
Vacuum casting was actually conceptualized to solve the air entrapment problem. Researchers were able to learn that under the normal casting process, the air present in molds tends to get trapped in the final solid structure and air pockets are formed inside that compromises and weakens the overall structure of the final product. Vacuum casting has been in the news because it solves this issue.
Vacuum casting was actually conceptualized to solve the air entrapment problem. Researchers were able to learn that under the normal casting process, the air present in molds tends to get trapped in the final solid structure and air pockets are formed inside that compromises and weakens the overall structure of the final product. Vacuum casting has been in the news because it solves this issue.
Vacuum Casting: The process
The process of vacuum casting consists of multiple stages. The overall process is labor-intensive but still relatively fast-paced and easy to manage. The process is described as stage-wise as follows:
1. Creating a master model
First of all, a master model has to be created or obtained on the shelf. The master pattern can be an industrial part or one created through rapid manufacturing techniques like 3d printing or CNC machine tools. Parts created through 3d printing are created using the stereolithography/SLS techniques. It must be ensured that the master model used has the correct dimensions so that the final casting parts have the desired dimensions as well.
2. Producing the mold
Liquid silicone is used to create silicone mold. Once the master model is put inside the casting box, liquid silicone is poured all over it and then it is left to cure in an oven. The cured liquid silicone mold is then cut open and the master mold has removed that leaves behind an empty cavity. The empty cavity is of the exact shape and dimensions as the original master pattern. Silicone molds can typically be used 15-20 times.
3. Making the casting copies
Now suitable resins (or polyurethane that are like rubber) are mixed to ensure that the mixture has the same properties as the industrial part. The manufacturers have a list of material data sheets that have all the information about the composition and properties of the materials they used for casting. They use that information to produce a resin that best resembles the properties of the master part. The mixture is poured into the empty cavity to form the desired finished mold or product. The resin is then cured in a vacuum so that no air bubbles are trapped.
