The article discusses the automation of the tool wear monitoring for collecting statistics on the cutting process and taking into account its variability in the design of technological processes for the manufacture of engineering products. It is proposed to use the diagnostic capabilities of modern CNC machines. The main methods of tool wear monitoring are considered: a direct method using optical or electromechanical methods or an indirect method using measurement of the load of drive motors or oscillations of a technological system. The automation of the direct tool wear monitoring method on the Heidenhain TNC 620 CNC system is presented. The change in load on a main motion drive during a tool wear is shown on a practical example. The experimental setup for estimating cutting tool wear by vibration level is proposed.