LARGE AREA THREE DIMENSIONAL PRINTER

A system for manufacturing a three-dimensional article includes a resin vessel, a light engine, a support scaffold, and a positioning actuator. The resin vessel includes an opening closed by a transparent sheet with opposed upper and lower surfaces. The light engine is disposed below the transparent sheet and is configured to transmit or project radiation up through the transparent sheet for selectively curing layers of the resin over a build plane. The support scaffold includes at least one ridge having an upper surface that contacts the lower surface of the transparent sheet to reduce an unsupported width. At a first lateral position the scaffold blocks the radiation from reaching a first blocked region of the build plane. The positioning actuator is configured to laterally move the scaffold from the first position to a second position to allow radiation to reach the first blocked region of the build plane.