The experimental tool of the Plastic Institute Lüdenscheid for capturing the demolding forces represents a measuring instrument with which the demolding-relevant surface effects between the tool surface and plastic melt can be evaluated. By means of a torsional movement of the mold insert, which can be exchanged through a quick-change system, the torque necessary for detachment (or "demolding") is recorded over time. In this process, the insert rotates by 180 degrees. During the rotational movement, a surface pressure between the mold insert and the molded part can also be set and monitored by means of measurement, so that swelling effects and their influence on the surface phenomena can be traced.