A Colorado physicist is putting his scientific expertise to a practical purpose -- using a 3D printer to build a Lamborghini with his 11-year-old son. Erie resident Sterling Backus and his son, Xander, 11, started work on their full-size, working model of an Italian supercar -- specifically the Lamborghini Aventador -- when the boy asked his father if it was possible. "One day I said to him, hey can we ...