The invention is directed to a method for additively manufacturing of a three-dimensional product using top-down stereolithography, wherein flowable, photopolymerizable material in a vat (50) is solidified in a locally selective manner by exposure from above, characterized in that a pressurized gas jet is directed to the surface of the photopolymerizable material, which pressurized gas jet is ejected by a pressurized gas nozzle of a blower (2) which is movable above the liquid level in the vat, wherein the pressurized gas jet is extensive in a direction transverse to the moving direction of the blower, and that by moving the blower with its pressurized gas nozzle across areas of the material surface to be solidify and acts on the surface in this manner, to smooth and level the surface. With such a method multi-component products may be built in which products a further component has to be built attached to an already existing component which (partially) protrude over the liquid level in the vat.