Vacuum Casting for Rapid Prototyping: All You Need to Know

25 Aug.,2023

 

With growing Industry 4.0 advancements, the trend of rapid prototyping is booming across multiple industries. This process streamlines design and production complexity, whether automotive, manufacturing, architecture or consumer products. Vacuum casting is an excellent method for rapid prototyping as it’s cost-effective and the design feedback is faster.

What is Vacuum Casting?

The working of vacuum casting is relatively easy. In this process, engineers first prepare a master mould. This master model is usually prepared using stereolithography (SLA) or selective laser sintering (SLS) or 3d printing technology. On the other hand, CNC is also a high-performance method to create the master module.

The image is used for illustration purposes. Zeal 3D Printing is not the owner or creator of the image.

Once the model is ready, it is kept in a vat and then covered with liquid silicone. After that, the silicone mold is cured and hardened. Once this is done, the silicone mold is injection polymer-based resin. Next, the complete casting process is performed under a vacuum to ensure no air bubbles are present in the cast resin. After the resin becomes solid, the mold is removed and reused to make identical copies.

Working Of Vacuum Casting Process in Rapid Prototyping:

We can understand the working of vacuum casting in the prototyping process in three easy steps:

Master Patterns

The polyurethane-based vacuum casting starts with a master pattern, which itself is a prototype. Engineers often use 3d printing or CNC machining for preparing these patterns as these techniques are fast. With these methods, it becomes easier for engineers to modify the design early if needed.

After the design patterns are ready, engineers need to prepare them carefully before they can be copied. The preparation process includes sanding, polishing to achieve the desired surface finishing. In addition, when multiple parts fit together in an assembly, independent testing is needed to ensure the proper finishing.

Preparing Molds

Once the patterns are ready, they are kept in a casting box later filled with liquid silicone. Next, it’s cured in an oven for several hours, and the silicone becomes solid, and the casting box is removed. After this, the mold is cut to remove the pattern, and it leaves an empty cavity with a copy of the original design.

Vacuum Casting

To prepare copies of the master pattern, you need to release the mold, with a feed tube leading into the cavity. After this, liquid urethane resin is poured into the mold and kept in a vacuum chamber. The sole purpose of the vacuum is to remove the air out of the cavity and force the resin into the entire volume of space. After this, the mold is heated in an oven, and the resin is cured. A perfect copy of the original design is obtained after reopening the mold.

Standard Specification

Below are the technical specifications that you need to know about vacuum casting:

  • Minimum wall thickness: Keep the wall thickness around 0.75 mm to ensure the mold is filled. And, to achieve the best results, keep the wall thickness of 1.5 mm.
  • Accuracy: It’s usually around ±0.3%
  • Lead time: Using vacuum casting, you can prepare a complex prototype in less than five days.
  • Maximum part dimensions: The size of the mold depends on the dimensions of the vacuum chamber and the volume of the product.
  • Quantity: It’s around 15 to 25 parts per mold.

Benefits Of Vacuum Casting for Rapid Prototyping

The image is used for illustration purposes. Zeal 3D Printing is not the owner or creator of the image.

Vacuum casting services offer several benefits to manufacturers who are looking for a quality prototyping process. Some of the key benefits are:

Higher Speeds

Mass production using vacuum casting can take a few weeks to complete. However, it becomes easy to prepare a prototype in a couple of days.

Superior Quality

Compared to other processes, the quality of the prototype is significantly higher with an exact design replica of the original part. In addition, this process helps manufacturers copy highly intricate details easily.

Cost-Effective

Manufacturers can duplicate hundreds of parts once the master model is ready without needing any additional support equipment. Thus, it makes the prototyping process accessible for small businesses.

Wrapping Up!

Vacuum casting is an ideal process to begin the prototyping and grow your business. Experience the best prototyping services with Zeal 3D Printing today. Upload your CAD file to get started.

If you have any questions on vacuum casting 3d printing. We will give the professional answers to your questions.