Our Related Manufacturing Capability
Why Choose RapidDone Vacuum Casting Services?
At RapidDone, we consider ourselves industry-leading manufacturers in the field of rapid prototyping and low volume production in China. When you trust us with your casting projects, you can be sure you’re getting the best quality possible.
Let’s share with you some of the reasons why you should choose us for your project:
1. Short Turnaround And Lead Times
We know speed is a priority when customers use vacuum casting. So, to deliver quality products in record times, we’ve paired some of the best equipment around with top-notch professionals.
2. Highly Qualified And Experienced Staff
Experienced technicians and design engineers make up our in-house staff. With this diverse team, we can optimize both the design and production to obtain the best possible final vacuum casting product.
3. Cost-Effective Quotes.
One of the things we pride ourselves on is helping customers balance cost and quality. No matter your requirements, our support staff will walk you through our offerings and help you find the best option. Our methods result in quotes that will not go over budget for your casting project.
4. Great Selection Of Product Finishes
At RapidDone, we recognize that getting a product market-ready requires a lot. To this end, we have a wide range of finishing processes for you to choose from to help achieve a premium result. Our finishing services include painting, polishing, printing, etc.
What Is Vacuum Casting?
Vacuum casting is a flexible method used in creating high-quality prototypes and low-volume end-use parts. It uses a casting process to produce copies of a high-quality master prototype from a silicone mold. Vacuum casting employs high-quality polyurethane resins as raw materials.
The technology for vacuum casting was originally developed in Germany in the 1960s. The technology was then sold to Japan, where it was applied in the booming automobile industry. It then spread to the rest of the world, where it has become a fixture in industry R&D departments.
How Does Vacuum Casting Work?
Transforming a CAD design to a product requires several steps. Let’s go through the steps in the production process At RapidDone.
1. Creating The Master Pattern
To begin the casting process, we need a master model from the CAD design. Creating this model can be done using additive manufacturing methods(SLA) or CNC machining. To get the best results, the model must be of very high quality.
After creating the model, its surface is processed and prepared to a high degree. These preparation processes can include painting, polishing, sanding, etc. The idea is to get a model that is as similar to the final part as possible.
2. Making The Mold
Next up, the model is suspended in a cast while the mold material-silicone rubber-is poured around it. It is then placed in an oven for several hours while the mold hardens around it. This process is known as curing.
After the mold has hardened completely, it’s split along a predetermined seam. The master model and the mold are separated, leaving a core and a cavity. The mold is put back together this time with a feeder tube and risers leading into it.
3. Part Casting
Next, we fill up the mold with the resin and place it in a vacuum. The purpose of the vacuum is to eliminate trapped air in the mold and force the resin into it. Trapped air can have adverse effects if allowed to linger in the mold.
After the pouring, the mold is removed from the vacuum and placed in an oven to cure the resin. After curing for some time, the mold is removed and reopened to bring out a perfect copy of the master model. After removing the part, we put the mold back together, and the whole cycle begins again.
4. Geometry Check
For most machine shops, the process ends here. But at RapidDone, we take things a step further to ensure maximum quality. We measure the final model and compare it to the CAD designs and the master model to ensure maximum accuracy.
Types Of Materials Used In Vacuum Casting
There are different types of materials to select from in vacuum casting. The sort of properties you want from the parts determines the material you use. At RapidDone, we offer a wide selection of different polyurethane resins to choose from depending on your needs.
These resins can approximate the physical properties of any material as needed. Let’s take a look at some of these materials and the benefits we offer:
- Polycarbonates–like polyurethanes and ABS–like polyurethanes have high structural strength and rigidity. These materials produce resilient, shock resistant parts.
- If flexibility and elasticity are requirements, then rubber–like polyurethanes and propylene–like polyurethanes are the right materials for the job. They have high tear resistance and are cheaply available.
- For parts that need to survive harsh temperatures, PMMA–like polyurethanes, and polycarbonates–like polyurethanes should be the first choice. They combine excellent structural strength with superb thermal characteristics.
Applications Of Vacuum Casting
Vacuum casting has many applications in different industries. Whether it’s used for prototype creation or low volume production, it offers many advantages. Let’s take a look at some of its uses in various industries:
1. Design and Marketing Industry
This industry benefits the most from the speed and high quality offered by vacuum casting. Design engineers use vacuum casting to create high-quality prototypes that are displayed in front of customers and investors. With these prototypes, they can conduct market tests without committing to full-scale production.
2. Electronics Industry
In the electronics industry, vacuum casting displaces conventional manufacturing methods like injection molding when high quality is required. Premium plastic housings for electronics like laptops, headphones, etc are examples of products made using vacuum casting.
3. Medical Industry
The medical industry is a big market for Vacuum cast parts. Medical equipment like prosthetics, dental molds come with strict standards and customization requirements. This means they cannot be mass-produced. They need to be produced in small, custom batches.
In this case, vacuum casting offers a cheap, reliable alternative to methods like CNC machining. The equipment can be produced at lower costs while maintaining high compliance to the set standards.
Vacuum Casting Technical Specifications
At RapidDone, we pride ourselves on being industry leaders in the field of vacuum casting. To maintain that standard, we always aim to provide the best quality possible. It shows in the standards we set for ourselves in our technical specifications.
Let’s have a look at the technical specifications.
- Lead times: We can produce up to 25 copies within 5 working days.
- Standard accuracy: Our parts have an accuracy of ±0.3% (with a lower limit of ± 0.3 mm on dimensions smaller than 100 mm).
- Minimum wall thickness: For proper mold filling, we recommend a wall thickness of at least 0.75mm. To get the best results, opt for a wall thickness of at least 1.5mm.
- Maximum part dimensions: The mold’s size is limited by the dimensions of the vacuum chamber, and your product’s volume. For more information about our chamber’s size, contact us.
- Typical quantities: From 15-25 copies per mold (It all depends on the part’s complexity and the mold’s material).
- Surface Finishing: High-quality textured surface finish.
- Colouring: Different color pigments are available. Transparent resins are also available.
How Much Does Vacuum Casting Cost
Customers coming to us usually show concern about the price of vacuum casting compared to other production methods. Considering what it brings to the table, vacuum casting is quite a pocket-friendly method.
At RapidDone, when preparing price quotes, there are a lot of options we present to the customer. We do this to ensure the customer gets the best possible quality without going over budget.
There are below factors that we consider for a vacuum casting quotation project. You can take this as a quick cost estimation when you come to your quoted project. If you want to have a solid price, you can contact our quotation team to get a price within 24 hours.
1. Master Model Fabrication
The master model is a key part of the vacuum casting process. For the best results, it must have the highest quality possible. Customers can choose between SLA printing and CNC machining when creating the master model. The cost and the quality between these two methods differ.
Also, the model might require additional finishing methods like painting, etching, and sandblasting. The sort of options you specify determines the price of the master model.
2. Mould Material
The mold material also plays a role in the final cost. The silicone we use to create molds comes in two versions- the local and the imported version. The imported version costs more, but it lasts for more production cycles than the local version. So, you have to choose.
3. Size And Complexity Of The Part
The size of the part also affects prices. For larger objects, the handling and labor costs will be higher. Also, larger castings use more mold materials. All these factors contribute to the final bill.
Structurally complex parts will also be more expensive. This is because complex parts are often harder to process and remove from the molds. Rough handling like this shortens the lifespan of the mold, thereby increasing the production cost.
There are different types of finishes available. They range from coloring or painting to laser etching the parts. The types of finishes specified can add to the production costs.
Finally, the last factor that influences the price is the volume. Like we mentioned before, vacuum casting more suitable for low volume production. As the quantity keeps rising, the unit cost will keep increasing until production becomes too expensive.
Advantages Of Vacuum Casting
Vacuum casting offers many benefits over other production methods like plastic injection molding. Let’s take a look at some of these benefits:
The setup costs for vacuum casting are small compared to other production methods. Unlike these methods, it doesn’t require much in the way of tooling or hard molds. The only costly object that needs to be prepared is the master mold.
It also beats out methods like CNC machining in electricity consumption and labor costs. Even the materials used (resins) are cheaper. All these cost savings add up to make it the cost-effective method.
2. Short Lead Times
Unlike other production methods, vacuum casting doesn’t require lengthy setup times. Within days of receiving the order, vacuum casting can produce the parts needed. Its speed can help meet tight deadlines or get the product to market quickly.
3. High-Quality Parts Obtained
Vacuum casting produces very high-quality parts. Fine surface details from the master pattern are reproduced easily. The final component can also go through several finishing processes to additionally improve its quality.
With a variety of materials available, vacuum cast objects can have any property. These properties range from the shockproof rigidity of ABS to the flexibility of rubber. With this, you don’t have to sacrifice functionality for cost when you use vacuum casting.
Also, during R&D processes, there can always be changes to the original design. With Vacuum casting, the cost of effecting these changes to the prototypes reduces compared to other methods.
Tips For Designing Vacuum Cast Parts
When preparing your casting’s design, it’s best to follow the proper design procedures to avoid problems. We’ve combined a list of tips to help you create the best possible product. Let’s take a look at these tips:
1. Keep Wall Thickness Consistent
When designing the part, make sure the wall thicknesses are consistent. Avoid overly thick sections as they can cause sink, which reduces the quality.
2. Keep Overhangs And Undercuts To A Minimum
Overhangs and Undercuts make it harder to remove to separate the cast from the mold. In using these features, you run the risk of damaging the mold and increasing production costs.
3. Be Mindful Of Tolerances
When casting mating parts, double-check the tolerances. Some part dimensions might need to be adjusted for shrinkage to ensure they fit after cooling.
FAQ In Vacuum Casting
Q1: Can Vacuum Casting Be Used With Metals?
A: No, it is only suitable for polyurethane resins. At the temperatures required to make metal flow(molten), the silicone mold will melt. This makes metals unsuitable for vacuum casting.
Q2: Can I Keep The Master Pattern After The Casting Is Complete?
A: After casting the product, we often discard the molds. Molds sustain damage during the casting. After the process, they have no value. But, if you require your master patterns back, please contact our team.
Q3: Which One Is Better For Me Between Vacuum Casting And Injection Molding?
A: Vacuum casting and injection molding both offer different advantages to customers. The method you select should be based on your needs. When going for complex parts in a large production run, the best option is injection molding. When going for a low volume order, and speed and accuracy are priorities, vacuum casting is the best bet.
Q4: Is Vacuum Casting Cheaper Than CNC Machining?
A: The answer depends on the order volume and the materials used. For quantities of more than ten pieces, vacuum casting is the cheaper option. At this number, the economies of scale of vacuum casting become more attractive than CNC machining.