Even though 3D printing is very magical, it cannot produce any object. For example, some internal complexities require multiple materials. And even though 3D printing is very magical, it cannot produce any object. For example, some internal complexities require multiple materials. And even though 3D printing is very magical, it cannot produce any object. For example, some internal complexities require multiple materials, And even though 3D printing is very magical, it can't produce any objects. For example, some internal complexity requires a variety of materials