A method, apparatus, and computer program product for identifying associations in a model of a structure. A number of fastener locations is identified in the model of the structure. A line segment extends through each of the number of fastener locations to form a number of line segments. The line segment extends a selected distance away from an associated fastener location in the number of fastener locations. A number of parts is identified through which the line segment extends to form a number of identified parts for a fastener for each of the number of line segments.