Vacuum casting works when a vacuum is applied to a small vented mold, forcing the liquid into the mold using atmospheric pressure. This process also removes air trapped in the mold, for a bubble-free casting. Vacuum casting machines are very good at casting small details and thin walls, making them ideal for casting delicate tools and equipment.

A vacuum casting system is often used to manufacture prototypes made of rubber, metal, or plastic. Vacuum casting can mimic parts made with injection molding. Metal jewelry, tools, and other objects are often made with vacuum casting.

1. A vacuum chamber is required to perform vacuum casting. These range in size and shape, so be sure the one you pick is big enough to hold your biggest project.

2. Vacuum casting provides a better surface finish due to the pressure applied during casting. This makes the product's surface smooth and shiny.

3. Sometimes products and prototypes require machining and finishing after vacuum casting to remove burrs and polish.

Action Steps
The best contacts and resources to help you get it done

Buy vacuum casting services from vacuum casting distributors

The vacuum casting process is often used by casting companies that perform a wide range of castings. Some companies work exclusively in metal or plastics, while others can cast a variety of materials. Make sure the company you choose casts the material you plan on using. Most vacuum casting systems use computer aided design to render your model first as a three-dimensional image.

I recommend: Find vacuum casting solutions at the Premier Die Casting Company, or from Modern Aluminum Castings.

Find materials for vacuum casting

The most common materials used in vacuum casting are metals like aluminum, zinc, and steel. You can also use other materials, like wax or plastic, in certain circumstances, depending on the type of item you want to create. If you need a specific alloy or casting material, you won't necessarily be able to rely on vacuum casting manufacturers to provide it. In these cases, its best to look elsewhere for casting materials.

I recommend: Check out RPM Engineering's selection of casting materials, or get your vacuum casting metals from F.W. Winter.

Purchase vacuum casting equipment to do it yourself

It's best to purchase a vacuum casting machine if you plan cast for an extended period of time. This saves you the cost of purchasing services from a vacuum casting distributor. However, you must pay for the machine, vacuum chamber and any training or employees necessary. Purchasing new or used vacuum casting equipment gives you more freedom in deciding what to cast when, and doesn't require you to wait for an opening in a service's busy schedule.

I recommend: Buy a vacuum pressure casting system from Advanced Process Technology, or check out vacuum chambers from Abbess Instruments.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  Some vacuum casting distributors give you a discount if you place a large order. In most cases, the larger the order, the heavier the discount. Even if your provider doesn't currently offer a discount, many companies are willing to make exceptions for large orders. Asking your distributor about mass-production discounts can save you money.