What is a punch-out in a 3D model typically used for?

A punch-out in a 3D model is primarily used to indicate a fastener location. This term refers to a specific area in a model where a void or opening is intentionally designed to accommodate fasteners, such as bolts, screws, or rivets. The punch-out feature is critical in ensuring that components can be properly assembled and connected in accordance with the design specifications. When planning fabrication and assembly, having clear indications of where fasteners are needed helps streamline the process and reduces the chances of errors during construction.

In this context, while representing design features can be a general purpose of 3D modeling, and creating complex shapes pertains more to the intricacies of the model itself, neither of these serves the specific functional purpose of a punch-out as effectively as indicating fastener locations does. Similarly, defining assembly instructions involves conveying additional information about the assembly process rather than representing specific locations for fasteners within the model.