An ink jet printer has an intermediate transfer drum that rotates past a print head and a downstream transfixing station. The surface of the drum is coated with a release agent. The print head ejects ink droplets onto the coated drum surface to form images thereon. The images are identified for either simplex prints or duplex prints. The transfixing station has separate simplex and duplex operating modes. A movable transfixing roll at the transfixing station is moved into and out of contact with the drum to form a periodic transfixing nip. The nip is formed with separate timing relationships with the approach of the leading and trailing edge of a transported recording medium and the approach of the image on the drum surface, depending upon whether a simplex or duplex print is to be transfixed by the nip.