Abstract: A vacuum covering method for covering a profiled surface of a base member with a sheet by effecting bonding between the sheet and the base member under vacuum, wherein the base member has a multiplicity of spaced vacuum grooves extending across the profiled surface. When air is evacuated from the vacuum grooves, the sheet is drawn by vacuum or suction down onto the profiled surface. The base member is injection-molded of synthetic resin and undergoes thermal shrinkage when it becomes cool after molding. With the vacuum grooves provided in the profiled surface, thermal shrinkage is distributed uniformly over the entire area of the profiled surface and does not generate shrink mark which may form a depression on a front surface of the sheet bonded to the base member.

Abstract: A vacuum forming apparatus has a first mold and a second mold, the first mold including a forming surface. The first mold has a hollow space defined therein and communicating with the forming surface through holes defined in the first mold. The hollow space is connected to a vacuum pump for developing a vacuum in the hollow space to attract a sheet against the forming surface through the holes. The second mold has a presser including a cylinder which displaces a cutter having a serrated trimming blade of the second mold. The presser has an upper groove which accommodates teeth of the serrated trimming blade. The first mold has a lower groove for receiving the teeth of the serrated trimming blade when it is displaced downwardly by the cylinder.