A disclosed additive manufacturing machine includes a fixed platform defining a work surface for supporting fabrication of a part and a housing defining a chamber over the work surface. A material applicator is supported on the housing for depositing material onto the work surface. An energy directing device is also supported on the housing and directs energy within the chamber to form a part. The housing is movable relative to the work surface therefore moves the energy producing device relative to the work surface to maintain a distance between the energy directing device and a surface of the part during fabrication.