Apparatus for layerwise manufacture of 3d objects and method of operation

An apparatus for the layerwise manufacture of one or more 3D objects from particulate build material, wherein the apparatus comprises a build area within a work surface and over which the one or more 3D objects are to be formed, wherein the build area represents the surface of the topmost layer, the apparatus comprising:

• a dosing device configured to provide an amount of build material to the work surface;
• a roller configured to pass over the build area while rotating about an axis of rotation to distribute the dosed amount of the build material over the build area to form a layer, the axis of rotation being perpendicular to the direction of distribution;
• and
• a cleaning device comprising a cleaning portion extending parallel to the axis of rotation, wherein the cleaning device comprises a plurality of perforations comprised at least within the cleaning portion, the perforations extending from a cleaning surface of the cleaning portion to an opposite surface of the cleaning portion opposite the cleaning surface;
• wherein the cleaning surface is configured to at least intermittently engage against the roller surface while the roller rotates, and wherein the perforations are configured to allow build material to pass from the roller through the cleaning portion to the opposite surface while the cleaning surface is in engagement with the roller surface.