How to carry out vacuum casting prototype processing?

With the rise of the manufacturing industry, more and more industries choose prototype models for the early development of new products. Prototype models play a crucial role in product development to verify whether there are any design problems. In the prototype industry, vacuum casting is one of the prototype processing methods

 

Vacuum casting is mainly used for small-scale prototype production, with the advantages of fast time, low cost, and very good market competitiveness. The materials used to make vacuum casting prototypes include ABS, PP,PC, What are the production processes of vacuum casting prototype, such as acrylic, soft rubber, and silicone rubber：

 

1. Prototype production

Before making silicone molds, it is necessary to make an original version, which can be produced through CNC machining or 3D printing. Prototype production is particularly important as it affects the accuracy and appearance of the product in the later stage.

 

2. Silicone mold production

Start making silicone molds, mix the silicone and curing agent evenly The appearance of mold silicone is a flowing liquid, with component A being silicone and component B being a curing agent. After mixing the silicone and curing agent evenly, a vacuum exhaust bubble process is carried out to reduce the generation of bubbles and ensure the density and appearance of the casting.

 

3. Silicone curing and product demolding

Pour the silicone that has been evacuated and purged of bubbles onto the product by brushing or pouring (note: the product or model to be replicated before pouring the silicone must be coated with release agent or isolation agent), then brush the silicone onto the product, place the mold in a specific oven for curing, and after curing is complete, remove the casting to complete the product demolding.

 

4. Post processing of castings

The products produced by vacuum casting are usually subjected to trimming, polishing, and smoothing. Depending on the needs of some customers, they may also require painting, polishing, spray coating, and screen printing to ensure that the appearance meets customer standards.

 

About Yangchi Vacuum Casting Manufacturing Case

Yangchi has produced a batch of robot shell components for a professional robot research and development company. In the demand for small and medium-sized batches, vacuum casting is undoubtedly the best choice.

Our steps for manufacturing robot shells

-Confirm the drawing design

Our technical team will analyze the drawing structure using DFM, confirm the CAD design with you, and create the original template through CNC/3D printing.

-Silicone mold manufacturing

Using product prototypes (rapid prototyping parts, CNC prototypes) to create silicone molds in a vacuum state, and casting them using materials such as PU, ABS, etc. in a vacuum state, in order to clone replicas that are identical to the product prototype.

- Casting parts

Pour the silicone solution into the mold, cure it at a constant temperature, and then cast the product.

-Inspection and delivery

After all the accessories are cast, we will assemble the complete product and proceed with the next step of surface treatment. The entire production cycle can be completed within 3 days.

 

Advantages and disadvantages of vacuum casting:

There are many advantages to vacuum casting processing, as follows:

  

(1) Suitable for small batch product processing and production, once an original version is made, it can be replicated based on the original version, while CNC machining requires a lathe to make prototypes one by one.

(2) Low cost and relatively short product production cycle. Less waste and much lower processing costs compared to CNC machining and 3D printing.

(3) The probability of processing failure is low. As long as there are no issues with the original version, the replica will naturally not make any mistakes.

(4) Good mold making operability. After solidification, the soft molds are transparent or semi transparent, with good tensile strength and easy cutting and parting.

(5) Good repeatability. The silicone used for molding has good flowability before curing, and with vacuum defoaming, it can accurately maintain the detailed structure and decoration of the model.

However, the vacuum replica prototype also has disadvantages, such as being prone to shrinkage and deformation, as it will shrink after being heated at high temperatures and cooled, resulting in deformation, with a general error of about 0.2mm. In addition, vacuum casting prototypes can generally only withstand high temperatures of around 60 degrees Celsius, and their strength and hardness are also lower than CNC prototypes.

 

Summary

The vacuum casting process has advantages such as small batch size, low cost, repeatability, and good operability, and is widely used in the manufacturing industry. At Yangchi, we have over 10 years of casting experience and have established friendly cooperative relationships with numerous enterprises. We can provide you with the best service experience and high-quality products. You can upload your CAD drawings and let us serve your project!