The rapid injection moulding process is almost the same as conventional injection moulding. The major difference is about how tooling is manufactured. Rapid moulding is used for a smaller number of runs, so it can use soft materials. They have strength similar to steel, but it is much easier to polish them.
The dies of rapid injection moulds can be easily redesigned. They use a lot of:
The manufacturing of design ensures:
Under high pressure, a liquefied resin is injected into the cavity. It will make sure that the part has no pores. Also, the quality of the final material is the best.
The finished surface of the moulding part depends on the quality of the mould. The cavity is manufactured by CNC milling. After that, some finishing operations are also applied. One of the most common among them is polishing. To sharpen the inner corners of the cavity, EDM cutting is used.
As compared to other prototyping techniques, injection moulding offers great precision. Rapid injection moulding is limited only by mould precision.
Many prototyping techniques don’t consider the material. For manufacturing single-digit batches, this can be applied. Some products require huge testing. Let’s take an example of a medical prototype.
Their last testing step involves giving out the product to the customers for regular life tests. This means that you will need thousands of samples and 50% of the blank material.
Most of the prototyping processes excel at creating a few parts. Rapid injection moulds are not durable as compared to conventional ones. But, as compared to many prototyping processes, rapid injection moulds can withstand many more runs.
3D printing, when done with a different plastic, requires a change of the entire system. The cartridge should be changed with the blank material. This changes a lot of settings to print the same part from another plastic. When the case gets worse, you will need a completely different component. This thing is unnecessary when it comes to moulding.
Mould is made of high-grade aluminum with many higher properties as compared to plastic. That’s the reason any material can be used with the mould.
Prototyping techniques in comparison with mass production are not that effective. The machining processes of mass production are optimized to minimize blank setup and trajectory. When you make a few parts in a larger batch, the high processing time is fine. Rapid injection mould technologies have the shortest processing time as compared to other prototyping techniques.