Over the past few years, digital fabrication has been utilized in technology laboratories to emphasize hands-on learning processes in technology and engineering education. Recent studies indicate that hands-on activities can help students connect with science, technology, engineering, and mathematics (STEM) disciplines and develop key skills required in the 21st century. However, some argue that introducing 3D printing technology in schools could reduce pragmatic engagement and cause affective loss of hands-on interests. To explore the use of 3D printing machines in technology and engineering education, this research developed a STEM-based vibration isolator activity using a 3D printer and repetitive modeling. A nonequivalent control group design was employed in this research, and 192 Taiwanese high school students participated in this study. The conclusions are: (1) repetitive modeling in the STEM-based design activity enhanced student imagination; (2) repetitive modeling was effective in developing high school students' interest in technology and engineering careers; and (3) repetitive modeling, engineering design, and "conceiving imagination" were significant predictors of the students' final products. These results suggest a benefit to high school technology education of using 3D printers in a STEM-based vibration isolator design activity with repetitive modeling.