Abstract: The finishing of workpieces is one of the defining elements of product quality. For this reason special attention should come to the study of surface smoothing operations, given their decisive role in obtaining high dimensional and geometric precision. One of these finishing processes is lapping. The paper presents a technological processor for plane surface lapping, a useful instrument for technology designing engineers. The technological processor allows the user to rapidly determine the duration of machining and  the height of the layer of removed material.