A 3D printer comprises a platform, a dispenser and a light source. A heating element heats a material and a nozzle extrudes the heated material onto the platform to form a first layer, having a first shape specified by one or more digital files. The first shape corresponds to a first minimum line width based on a diameter of the nozzle. The light source emits a light beam that is directed onto the first layer according to the one or more digital files to cure a portion of the first layer to create a first cured layer that corresponds to a second shape of a 3D object specified by the one or more digital files. The light beam has a beam diameter that is smaller than the diameter of the nozzle, and the second shape has a second minimum line width that is smaller than the first minimum line width.