What step in the basic AM procedure must engineers or operators complete before creating an STL file and G-code file?

The correct choice is to create a 3D CAD model of the part because this step is fundamental in the additive manufacturing (AM) process. Before any AM part can be fabricated, a detailed digital representation of the object must be made. The 3D CAD model serves as the blueprint for the part, capturing all necessary dimensions and geometrical details that will dictate how the part is manufactured.

Once the CAD model is completed, it can then be converted into an STL (Stereolithography) file, which is a widely used format for 3D printing. The STL file translates the 3D model into a format that an AM machine can read, enabling the creation of G-code files necessary for actual production. Without a proper 3D CAD file, it would not be possible to generate the STL file and subsequently the G-code, making this step indispensable in the AM workflow.

The other options mention important aspects of the AM process, but they occur after the CAD model has been established. Determining material properties helps in selecting the right materials for printing, preparing the work area ensures a suitable environment for AM operations, and calibrating the machine is essential for ensuring precise print quality; however, none of these steps can take place