Draft Sight is a free 2D system by Dassault, the makers of SolidWorks.
Free and fairly easy to learn, if your desire is 2D working drawings it is more then sufficient for the purpose, if however you want isometric or solid modeling capability it will not be for you.
Google Sketch Up will do but in the limited time that I played with it I'm not sure that it will output a well done dimensioned line drawing for printing.
You are showing your age, drawings haven't been blue for decades (-: