A backgauge is a mechanical system, normally attached to a brake press.
Its main function is to interface with the brake press computer numerical control (CNC), moving along several different axes in order to precisely position a piece of metal for forming.
Each of these individual axes is controlled by a separate electric motor.
Often a brake press is sold to a customer in conjunction with a backgauge.
On an extrusion saw, a backgauge is responsible for feeding material at exact amounts past a saw blade.