This paper focuses on how the notion of a trajectory of identification can be traced between different timescales and different sets of data that pertain to the student. The development of a specific student's trajectory is traced through his ability to talk-engineering along two different timescales: the entire four years of undergraduate education and the final 10-week quarter that includes work on the senior design project. This study is based on results from longitudinal ethnographic interview texts and video data from senior design and capstone projects.