Line bending is a process whereby a plastic sheet is heated along a small area until the plastic reaches its forming temperature, the sheet is then placed into a cooling jig that is designed to cool the plastic sheet into its newly formed shape.

This process is done using a line bender (also referred to as a strip heater) which is a machine that uses tensioned wire that is heated, when this wire is placed in close proximity to the material the plastic is heated along that bend line.