The best prototyping process for die casting depends on many factors. Most importantly, you have to consider the material restrictions of each process and the rigor of tests your prototype will be put through. If you’re looking for your prototype to mimic the mechanical and physical properties of your end component and withstand real-world testing, manufacturing your prototype with investment casting is the way to go.
Prototyping with investment casting entails either a short-run hard tooled wax pattern or a printed 3D wax, SLA, or PMMA pattern that is then run through the foundry just like any other production run.
Do you need a refresher on the investment casting process? Check out this quick video from our sister company, Signicast.
But what exactly makes investment casting a beneficial prototyping process for die casting components?
Prototypes with exact mechanical and physical properties
Unlike other processes, such as machining from solid or spin casting, investment cast prototypes have almost the exact same mechanical and physical properties to die cast components—like ultimate tensile strength, yield strength, and ductility. If you require your prototype to provide information on any of these characteristics, investment cast prototypes are extremely similar to die cast componentss
Additionally, the investment casting process can hold tolerances similar to die casting when sophisticated design features are included in the casting. The die casting process still holds the ultimate crown with tolerances as exact as ± 0.02 mm., but Signicast’s as-cast investment casting process is capable of +/- three standard deviations when a single point location is repeatedly measured—typically +/- .003 to +/- .004 per inch. However, tolerance capability is largely influenced by part configuration.
Wide alloy selection
With investment cast prototypes, you’re not limited in your material selection. Unlike machining, where you factor speed into your cycle time and cost, investment casting is compatible with virtually any alloy and your choice doesn’t change the speed of the process.
Do you need an alloy with specific strength, conductivity, elongation, or hardness requirements? Do you need to be able to test these requirements in a real-world setting before mass production? The wide alloy selection that is offered by investment cast prototyping will be able to accommodate these necessities.
Surface finish testing
Speaking of testing requirements, does your die cast component need to be able to withstand a corrosive environment or display high wear-resistance characterisitcs? Or would you like to test the longevity of an ornamental finish? Investment casting prototypes are an excellent option when you want to verify that your chosen surface finish or plating does not negatively affect the performance or the aesthetic of your end component.
Because of the nature of the ceramic shell used in the investment casting process, investment cast prototypes can maintain a repeatable standard surface finish of 125-150 RMS for most alloys. The smooth finish mimics that of a die cast component, and is therefore an accurate measure of how an additional coating or plating will perform on the part.
Why is a fully functional prototype the best prototype?
Testing with a fully functional prototypes allows you to effectively test for more demanding project requirements, rather than just proof of concept. The prototyping stage is important—it ensures a strong foundation for your product launch. We want to make sure that you get it right, the first time.