White light interferometry (WLI) is already used for the inspection of rotationally symmetric engine components. As part of the "AcDiCrackInspect" project, one goal is to enable the inspection of free-form components using WLI. For this purpose, the white light interferometer (WLI) used, together with the linear axis required for the measurement process, is to be mounted statically in space, while a 6-axis articulated robot handles the components. In order to place the WLI precision in front of possible damages in the required in order to inspect them, it is necessary to determine the transformations between the coordinate systems of the robot, the WLI and the additional linear axis of the WLI. Measuring these transformations by hand is too inaccurate for the very small measurement field of the WLI.