A heat sealing machine for applying heat at predetermined positions on a heat sealable film (21) placed over a compartmented tray (10) to seal the film to the tray on two substantially normal planes. The machine has a heated plate (30) adapted to bear upon the heat sealable film (21) on a first plane over the compartmented tray (10) and a spring loaded pressure plate (32) adapted to bear upon the heated plate (30). A supplementary heated member (36) is movable with respect to the heated plate (30) and has a pressure member (37) adapted to bear against the heat sealable film (21) over a surface of the compartmented tray (15) on a second plane.
