Method for determining position data for an apparatus for additively manufacturing three-dimensional objects

Method for operating at least one apparatus (1) for additively manufacturing three-dimensional objects (2) by means of successive layerwise selective consolidation of layers (17-19, 21-23) of a build material (3) arranged in a build plane (4) essentially extending in x- and y-direction, which build material (3) can be consolidated by means of an energy source, wherein the build material (3) is carried by a carrying element (9) of a carrying unit (8), wherein the carrying element (9) is essentially movable in z-direction, wherein the z-direction is essentially perpendicular to the x- and y-direction, characterized in that position data relating to an x- and/or y- position of the carrying element (9) are determined for at least one z-position.

Apparatus (1) for additively manufacturing three-dimensional objects (2) by means of successive layerwise selective consolidation of layers (17-19, 21-23) of a build material (3) arranged in a build plane (4) essentially extending in x- and y-direction, which build material (3) can be consolidated by means of an energy source, wherein the build material (3) is carried by a carrying element (9) of a carrying unit (8) of the apparatus (1), wherein the carrying element (9) is essentially movable in z-direction, wherein the z-direction is essentially perpendicular to the x- and y-direction, comprising a calibration unit (13) adapted to determine position data relating to an x- and/or y- position of the carrying element (9) for at least one z-position.