A process for fabricating a curved vehicle impact sandwich beam including a micro-truss structure. The method includes positioning a mold in contact with a curved bottom facesheet so that the mold and the bottom facesheet define a reservoir. The reservoir is filled with a liquid photo-polymer resin and a mask is positioned over the reservoir. A series of UV light sources are provided on a mounting member relative to the mask and the mounting member is flexed to conform to the shape of the bottom facesheet. Light from UV sources shines through apertures in the mask to cure and form polymerized struts in the reservoir to define the micro-truss structure formed to the facesheet.