Given the application of a multiple regression and artificial neural networks (ANNs). this paper describes development of models for predicting surface roughness. linking an arithmetic mean deviation of a surface roughness to a torque as an input variable. in the process of drilling enhancement steel EN 42CrMo4. https://www.spidertattooz.com/Fanimation-MAD8514-TriAire-52-Indoor-Outdoor-Ceiling-Fan/