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.roneverhart.com/HGST-Ultrastar-7K6000-HUS726040ALS214-4TB-7-2K-RPM-SAS-12Gb-s-512n-128MB-3-5-SE-Hard-Drive/