Recent technologies are offering the power to share and grow knowledge and ideas in unprecedented ways. The CogEx software platform was developed to take advantage of the digital world with innovative ideas to support designers work in both industrial and academic contexts. This paper presents a qualitative study on the usage of CogEx during capstone design projects in mechanical engineering. It explores its potential to eventually supersede a paper logbook. This study combines three pilot projects where 15 undergraduate students used CogEx for one semester and discussed their experience in a final interview. The focus is limited to individual usage in this study. Results support that the platform has a good potential for engineering design education by replacing the paper logbook. The "extended concept mapping" structure was efficient to organize design work, and although the "concept-knowledge" separation needs refinement, it has good potential in building designer knowledge base.