3D printing is being used by more and more automotive applications. It can be applied to all applications from internal components to the entire chassis. Even tires can be printed in 3D. This technology has many advantages, including lighter parts, less scrap, faster manufacturing time, lower costs, and more. However, some cars have poor 3D printing results. Because 3D printing is a layer-by-layer process, the final product often shows these layers.
Of course there are exceptions. Some materials and post-processing techniques essentially eliminate any signs of layering in glass and plastic parts. But in general, 3D printing is not the technology of choice for achieving a perfectly clear surface. For this reason, most manufacturers turn to CNC machining. CNC machining sculpts objects from solid blocks, so there is no layer line to produce clear components that can be used in headlights, taillights, or interior lights in cars.