KOMA-TAISEN is a battle tournament between spinning tops. The tournament is sponsored by a non-profit organization for manufacturing companies and has been held in various cities in Japan since 2012. The tournament attracted the interest of educational institutions with machine shops and small and medium-sized enterprises because the World Championships were held in 2015 and 2020. The battle of tournament competes for the length of time that two spinning tops are spinning in a small circular ring. The player of each team must stand on the ring side and rotate the spinning top with only the fingers of one hand. The spinning top must be manufactured to realize unique ideas under the constraints of specific dimensions. Therefore, each team is required to have advanced processing technology to finish the dimensions and center of gravity of parts with high accuracy. In this project, students who were interested in machining participated in KOMA-TAISEN held in Miyagi prefecture from 2018 to 2020 with the goal of winning the student category. The purpose of this project was to learn advanced machining technology using machine tools such as lathes, and to learn the workflow by PDCA cycle.