An automated scraping system with a machine tool and an image processing system has been developed in previous studies. In order to use the system as a highly precise and efficient system, it is necessary to intelectualize the scraping system like a skilful worker. This paper describes an investigation (digitalization) of a scraping operation by a skilful worker so that future studies can achieve effective and intelligent scraping system by means of the digitalized operation. In each step or the scraping operation, an image of the scraped workpiece with black bearing was obtained by a digital camera with a contrivance of imaging method and the information of the black bearing was obtained by image processing from the image. Moreover, a 3-D shape data of the workpiece was measured by a laser displacement meter on a machine tool. In the evaluation of the scraping operation, a hieght histogram of a 3-D shape data is useful. As a result, a strategy for smart and intelligent scraping was guessed from the investigation.