Its' a manufacturing
process in which a liquid material is usually poured into a mold
, which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a casting
, which is ejected or broken out of the mold to complete the process. Casting materials are usually metals or various cold setting
materials that cure
after mixing two or more components together; examples are epoxy
. Casting is most often used for making complex shapes that would be otherwise difficult or uneconomical to make by other methods.
3D printing and injection molding aren't really competing technologies so much as they are complementary. 3D printed prototypes are not typically finished parts. Most FDM machines utilize either ABS or PLA plastic (and others!) which is more often than not a different product than the final manufactured part will be made from.
Whether you are interested in how to make a mold for reproducing a sculpted figure, an antique picture frame, an industrial pattern, an architectural molding, a fossil, animal skin (taxidermy), the texture of a piece of fabric, or a toy, you start by making a rubber mold. Whether you want to make one or one thousand reproductions of an original, you can do it using a mold. Whether your original model is made from clay, wax, plaster, sand, concrete, stone, metal, bone or almost any material, making a mold makes it possible to reproduce that model – exactly.
Moldmaking with desktop 3D printing allows engineers and designers to get much more functionality from their 3D printer, beyond prototyping alone.
Learning how 3D printing can be used for injection molding opens up a world of production materials, and provides the ability to produce short run batches and test mold designs prior to committing to expensive tooling.