Abstract: A system for forming an article includes an apparatus for stacking successive sheets of a polymer mixture and selectively irradiating each sheet with an electron beam deflected to trace the configuraiton of an incremental heighth of the article. The polymer mixture may include a polymer resin mixed with a reactive diluent and, if required, an initiator. The stacked sheets form a matrix which supports the article as it is being shaped. After integration of all incremental heighths of the article, heat or chemical dissolution is employed to remove the matrix. The sheets may be a laminate of a stratum bonded to a substratum. The substratum is easily compressed under heat to reference the level of the upper surface of the sheet irrespective of thickness variations of the sheet. To compensate for beam intensity absorption, the substratum is formulated with increased sensitivity. Successive sheets are heated while being transported to a platen which is positioned beneath an electron gun.