If you want to know what is the most economical way to make a prototype? Then you should try vacuum casting. In vacuum casting, you need to have the right and optimal temperature to cure the material. For resin, when the vacuum pressure time is 5 minutes and the mold temperature is 60 degrees Celsius, you need 30 degrees Celsius to minimize shrinkage.
Vacuum casting is the same replication using silicon molds. The use of silicone molds for plastic vacuum casting was developed in a German university in the 1960s. What are the benefits of vacuum casting for your company? Continue reading this article to find out.
1. What is Vacuum Casting?
Vacuum casting is an elastomer casting process that uses a vacuum to suck any liquid material into the mold. When vacuum casting is used, air trapping is a problem with the mold. In addition, this process can be used when there are complex details and cuts on the mold. In addition, if the material used to make the mold is fibre or reinforced steel wire, it is also applicable.
Sometimes, vacuum casting is also called thermoforming, because the process of manufacturing involves rapid prototyping, and the plastic sheet is preheated. These materials are preheated in an automatic vacuum casting machine until they become soft and flexible.
2. Why Choosing Vacuum Casting?
The result of the vacuum casting process is a high-quality product compared to injection molded components. Vacuum casting models are often used for functional testing and marketing purposes. The final product has such a good ending, this technology has attracted a large number of viewers. The finishing method of vacuum casting is unmatched by any other process.
1) The product has high precision and fine details
When you use silicone as a mold and moldy to your product. It ensures that the final product has a great interest in details. The final product looks just like the original product.
Every interest in information is considered and also considered. Even if the original product has the most complex geometry, the final product looks like the original product.
2) High-quality products
The products produced by the vacuum casting process are of high quality. In addition, the use of resin allows you to choose the ideal product for the final product produced.
This enables you to have more flexibility, hardness, and hardness options in your project. Also, considering that the product used plays an important role, this has an excellent effect on the final appearance of the product.
3) Lower Production Costs
It is more cost-effective to use the vacuum casting process to make products. This is because this process uses silicon to make molds and mold. Compared with aluminium or steel, silicone resin has a lower cost and can produce excellent end products.
In addition, this material allows you to make more products from mold and mildew. This makes the process more budget-friendly compared to using 3D printing.
4) Fast Delivery
This method is fast, and it takes less time to complete the completed project. You may need 7 to 10 days to make about 50 operable model parts. This technique is amazing when you make a large number of items. In addition, if you can complete the task before the deadline, that would be great.
3. How Does Vacuum Casting Work?
Casting of polyurethane must be carried out under vacuum to guarantee the excellent characteristics of mechanical strength and surface finish typical of this technology.
Typically, the master is obtained by 3D printing, possibly using a technique that provides a good surface finish, such as stereolithography, and depending on the properties of the piece to be obtained (mechanical strength, transparency, colour, elasticity, weight, conductivity, flame retardancy, etc.) choose cast polyurethane.
Alternatively, the master can also be achieved by other techniques (CNC, hand modelling), it can also be made from a commercially available detail, an old product or a piece of art. Even casting materials can be of different types: Epoxies, waxes, ceramics and composites can replace polyurethane.
Vacuum casting can be used to assemble different materials, for example, to incorporate bushings, pins, different types of inserts, electronic boards, and also to overmolding two different plastic materials or one plastic and one elastomer. In contrast, compared to mass-production solutions such as injection molding:
4. Vacuum Casting Process
The vacuum casting process follows different process stages to manufacture raw materials and complete finished products. Everything takes place in a casting vacuum chamber. Let’s see the step-by-step process of how vacuum casting works:
1) Have a high-quality master model
The vacuum casting process requires you to have a high-quality master mold. The high-quality master model can be the industrial component itself. In addition, you can use a model created using stereolithography, which is an example of application prototyping.
You should always make sure that the master model used has the correct size and appearance. This is to ensure that no defects are transferred to the model prototype after the completion of the process.
2) Cure Process
Then, the master model is encapsulated in a two-part silicone rubber mold. The mold is cured at a high temperature to ensure that the two parts stick together. In this way, the mold can be stronger and more durable.
After the mold is cured, it is cut open to expose a hollow space in the centre, which is consistent with the precise dimensions of the main model. After the mold is cut into two sections, it is placed in a vacuum chamber. Then, fill the specified material in the mold to make the product.
3) Filling The Resin
You should fill the mold with the specified material. This resin has the characteristics of industrial material. Resin materials are usually mixed with metal powders or any coloured pigments to achieve aesthetics or specific functional properties.
After filling the mold with resin material, it is placed in a vacuum chamber. Place in a vacuum chamber to ensure that there are no bubbles in the mold. This is to ensure that the final product is not destroyed or damaged.
4) Final Cure Process
The resin is put into the oven for the final curing stage. The mold is cured at a high temperature to ensure that the material is strong and durable. The silicone mold is removed from the mold so that it can be used to make more prototypes.
After the prototype is taken out of the mold, it is painted and decorated. Painting and design are used to ensure that the product has a gorgeous final appearance.
5. Benefits of vacuum casting
Vacuum casting is more economical than 3D printing or injection molding. This allows you to produce more items at a lower cost. Visit this website and learn more about vacuum casting and the use of silicone molds and mold using this extraordinary modern technology.
1) Better than injection molding
Because injection molding is more commonly used than vacuum casting, many organizations may not even consider the vacuum casting process of their parts. However, in some specific cases, silicone-based surgery is more worthwhile and may be of higher quality.
2) Quantity
For a large number of components, it is difficult to see injection molding. Although the set-up price of injection molding is high (even with rapid mold), the equipment cost is very low. This means that when a company needs hundreds or thousands of duplicate parts, the upfront cost of installation can be easily compensated by saving each part.
On the other hand, not every organization needs hundreds or thousands of copies of a component. When fewer parts are required, vacuum casting may be a better choice, as installation costs are greatly reduced.
3) Detail
Since molds are usually made of high-quality metal, shot peening can develop more complete parts compared to vacuum casting. Therefore, for highly complex parts, shot blasting is a better choice.
For less complex parts, especially those that only need to be manufactured in small quantities, vacuum casting can be more effective. This is not a simple and affordable alternative: vacuum casting can use extremely smooth surfaces, which means direct components may look better when vacuum casting is used.
4) Rate and version
Vacuum casting reduces configuration costs and has a good knock-on effect. If the design needs to be modified at any stage in the manufacturing process, changing the vacuum casting mold and mold is much easier and more affordable than redesigning the mold or reusing the mold for injection.
Generally speaking, this means that in the early stages of development, vacuum casting is usually a better choice. In fact, organizations often use vacuum casting to make very early models before creating end-use components or late-stage prototypes using injection molding.
Importantly, producing molds and molds for vacuum casting is much faster than creating molds for pellet casting, which means that vacuum casting is usually more suitable for very small numbers of time-sensitive prototype tasks. (The larger the batch, the faster the injection molding.)
5) Material considerations
Even if all indications indicate vacuum casting, we must remember that some prototypes—especially those that will undergo physical screening—need to be as close as possible to the end-use part. Therefore, if a useful part will eventually use injection molding, it may be beneficial to prototype using the same process, even if the cost is higher.
6. Vacuum Casting Material
We offer 26 carefully selected polyurethanes, similar to rubber, PP, ABS, and PC. These materials provide excellent various properties and the possibility of matching colours and casting transparent components. If you are looking for a specific finish, our skilled vacuum casting post-production team will meet your requirements. Contact us for more detailed information to find the best material for your project.
With high quality products and considerate service, we will work together with you to enhance your business and improve the efficiency. Please don't hesitate to contact us to get more details of vacuum casting 3d printing.