Method of manufacturing an object by stereolithographic 3D printing, wherein the object is built on a building platform layer-by-layer to obtain a stack of structured layers, wherein each structured layer is obtained by the steps of: - providing an unstructured layer of photosensitive resin, and - selectively projecting light onto the unstructured layer according to a desired pattern, thereby curing the photosensitive resin to obtain the structured layer that is structured according to the pattern, wherein the stack of structured layers comprises a first pair of adjoining structured layers, characterized in that at least a first film (32,33) of removable material being different from the photosensitive resin is placed onto a first structured layer of said first pair of adjoining structured layers by ejecting drops of the removable material from an ejector, whereafter a second structured layer of said first pair of adjoining structured layers is built on the first film (32,33) of removable material, thereby arranging the first film (32,33) of removable material between the first and the second structured layers of said first pair of adjoining structured layers, and wherein in a post-processing step said first film (32,33) of removable material is subjected to a physical and/or chemical process that causes the first film (32,33) of removable material to disintegrate or lose its stability and the removable material is removed from the object. - providing an unstructured layer of photosensitive resin, and - selectively projecting light onto the unstructured layer according to a desired pattern, thereby curing the photosensitive resin to obtain the structured layer that is structured according to the pattern, wherein the stack of structured layers comprises a first pair of adjoining structured layers, characterized in that at least a first film (32,33) of removable material being different from the photosensitive resin is placed onto a first structured layer of said first pair of adjoining structured layers by ejecting drops of the removable material from an ejector, whereafter a second structured layer of said first pair of adjoining structured layers is built on the first film (32,33) of removable material, thereby arranging the first film (32,33) of removable material between the first and the second structured layers of said first pair of adjoining structured layers, and wherein in a post-processing step said first film (32,33) of removable material is subjected to a physical and/or chemical process that causes the first film (32,33) of removable material to disintegrate or lose its stability and the removable material is removed from the object. wherein the stack of structured layers comprises a first pair of adjoining structured layers, characterized in that at least a first film (32,33) of removable material being different from the photosensitive resin is placed onto a first structured layer of said first pair of adjoining structured layers by ejecting drops of the removable material from an ejector, whereafter a second structured layer of said first pair of adjoining structured layers is built on the first film (32,33) of removable material, thereby arranging the first film (32,33) of removable material between the first and the second structured layers of said first pair of adjoining structured layers, and wherein in a post-processing step said first film (32,33) of removable material is subjected to a physical and/or chemical process that causes the first film (32,33) of removable material to disintegrate or lose its stability and the removable material is removed from the object.