Welding of thermoplastics. The films made of these plastics are usually welded by welding with the use of rapidly changing electric fields, produced by special generators. At home, good welding results can be obtained with a hot copper or brass disc, rotatably mounted in a holder made of poorly conductive material. Rolling the slightly pressed disc over the edge of the folded foil makes it more plastic, and the pressure causes the connection. The discs heating temperature should be selected experimentally depending on the type and thickness of the welded foil. Approximate softening points for thermoplastics are given in the entry plastics.