Ever since the inception of modern manufacturing, engineers have followed a set of rules, termed design engineering, ensuring the reliability of the manufactured product. Computer-aided design (CAD) is the discipline of design engineering developed to assist through computers. Fundamentally, the foundation of CAD comprises geometric modelling, graphic design and computer graphics. Analogues to every other field of knowledge, research and development of design engineering are influenced by advanced technologies such as artificial intelligence (AI). This paper presents a comparative study of text-to-image-based AI models and then explains a method capable of automatically generating a complete three-dimensional (3D) model solely based on text prompts. Performance index of the text-based AI model to generate 3D models of different mechanical components is presented through the confusion matrix method. It is also observed that the extensive dependency on the labelled data is not required for the diffusion-based model, and the text query-based complex 3D shapes can be created automatically through this method. Even though presently this technology is still in the preliminary research state, the results are promising. So, this technique can be applied to obtain complex 3D structures for engineering simulations, augmented reality (AR), virtual reality (VR), etc.