Casting 101

Modern investment casting is an industrial process based off of lost-wax casting, one of the oldest known metal forming techniques.

Watch the following video to learn more about our investment casting process.


What is an “Investment Casting”?

Investment casting is a process in which a wax cluster is covered in a ceramic slurry. Once hardened the wax is melted out of the ceramic shell. The shell is then heated to 1,800 degrees Fahrenheit and molten metal is poured in. After cooling, the ceramic is then vibrated and blasted off the metal products. The products are then cut, cleaned and prepared for shipping.

What alloys can be poured as an investment casting?

As a general rule all ferrous and non-ferrous materials can be investment castings. Carbon, tool and alloy steel along with the 300, 400, 15-5ph and 17-4ph stainless steels are most commonly poured. Check our Alloy Selection Guide for details.

What size range of parts can investment casting produce?

Investment castings can range from a fraction of an ounce to over 1,000 pounds. Most investment casting foundries only cast parts up to 20lbs. RLM can cast parts up to 250lbs.

What is the tolerance range of parts that investment casting can produce?

Typically, a linear tolerance of +/- .005 in/in is standard for investment casting.

What kind of quality can I expect in the surface finish?

The ceramic shell is built around a smooth wax pattern, the finish achieved by investment casting is excellent. A 125 micro-finish is standard and even finer finishes can be achieved.

Isn’t investment casting expensive?

It is true that investment castings are usually more expensive than forged parts or those produced by other casting methods. Investment casting, however, makes up for this added cost by reducing the amount of machining and other secondary costs involved with other processes.

What about the integrity of investment casting?

Investment castings are used widely in applications that require parts to be x-rayed and meet definite soundness criteria. The integrity of investment casting can be far superior to parts produced by other methods.

What are the lead times I can expect when ordering investment castings?

Typically, 6 weeks for commercial grade and 8 weeks for ordnance. Deliveries can be negotiated and changed for the customers with special requirements

For more information about investment casting, please contact us. Or feel free to request a quote.