Engineering Drawing (ED) is one of the fundamental courses for various engineering disciplines. However, first-year engineering undergraduates often face difficulties in learning and solving ED problems that require visualisation of 3D objects. Conventional and modern teaching methods do assist the teaching-learning of a subject but do not guarantee the elimination of the learning difficulties, specifically related to visualising spatial relationships. Mental rotation (MR) skills play a major role in learning such concepts, and students should be trained for the execution of MR processes. This paper presents a 3D visualisation tool-based training programme where students practice MR processes. The training guides students through hands-on tasks, coupled with the cognitive steps of MR. We investigate the effect of the training on improving 253 engineering undergraduates' ED problem-solving performance by administering a pipeline of four research studies. Results show that the training successfully helps students in enhancing their ED problem-solving performance.