Download the free 2D and 3D practice drawing eBook containing the fully dimensioned drawing used in this video here: https://sourcecad.com/autocad-practice-drawings-with-pdf-ebook/
In this video, I have explained step by step method of making a 3D knob in BricsCAD modelling environment.
You can also download the trial version of Bricscad here https://www.bricsys.com/common/download.jsp