Silicone molds: what they are and what the process entails

The silicone molding (also known as polyurethane molding or vacuum casting) is a manufacturing process that uses silicone molds to produce plastic parts in a relatively simple way and without high costs or long lead times.

The silicone moldsprovide end-use plastic parts, rigid or flexible, with quality close to production level.

At Proto&Go! we use a part acquisition process via vacuum casting, which is built without expensive tools or those that consume too much production time. A master pattern made via CNC machining is always used, ensuring the part's finish and quality.

The vacuum casting process is carried out inside a vacuum machine where two components that will form the polyurethane are introduced into the chamber. Once the machine has completed the vacuum, the components are mixed and cast into the silicone mold.

This process is performed under vacuum with the main objective of facilitating the entry of the fluid into the mold cavity. In this way, any air resistance that could remain inside is avoided.

As a result, high-precision products with exceptional finish are obtained.

• Advantages and applications of vacuum casting with silicone molds
  
• Vacuum casting: What is the difference compared to other manufacturing processes?
  
• The future of vacuum casting: Promising trends

Advantages and applications of vacuum casting with silicone molds

Some of the advantages or benefits of vacuum casting are as follows: 

• Variety of materials and finishes
• It is an optimal process for low production volumes
• The finish quality is comparable to other technologies or part manufacturing processes
• Obtaining the first parts in a short timeframe
• Polyurethane parts are as resistant or hard as injection molded parts and stronger than 3D printed parts 

On the other hand, it is worth noting that vacuum casting of silicone molds has various applications. These parts are especially suitable for pre-production runs. This is due to their high quality level (comparable to parts produced by other methods).

Some of these applications or uses are:

• Pre-launch testing of new products
• Market study or testing
• Prototyping
• Short runs
• New product advertising

Vacuum casting: How does it differ from other manufacturing processes?

Vacuum casting is an ideal technology for serial production of parts with fine and complex details, while other methods, such as 3D printing, are excellent for prototypes and custom parts.

It is also a very cost-effective option for manufacturing silicone components in low-volume production compared to injection molding.

On the other hand, compared to other manufacturing processes, parts made via vacuum casting can be created and delivered in a matter of days (depending on size and quality). Therefore, it is a good option to choose this process if your lead time is tight.

In conclusion, compared to methods like CNC machining, polyurethane casting is a cost-effective option for producing reusable molds in just a few hours. Additionally, parts produced via this process fit perfectly and do not require additional steps like deburring or drilling.

Regardless, the choice of one method or another will depend on factors such as production volume, design complexity, required precision, and material. Each process has its advantages, and the best option is to choose the one that best fits the specific needs of the project.

The future of vacuum casting: Promising trends

Over time and with the continuous advancement of technology, it is highly likely that we will see many innovations in the field of silicone mold part manufacturing. Such innovations could include improvements in process efficiency, new materials, or design methods, among other factors.

The ability to produce parts with high quality, quickly, and that are also cost-effective will remain an important and key factor in design and manufacturing decisions (especially in terms of prototyping and short runs).

Additionally, customization and on-demand production are currently increasing, and vacuum casting of silicone molds is a perfect method to meet these needs.

For more information on silicone molds or to get a quote you can visit our website: Proto&Go!