The roller is used to get usable plates or sticks / wire from casted
material, or only to change material to the needed size. This will be reached
by decreasing the distance between the rollers after each complete passage
of the material trough the rollers. This will repeated until the desired
size is reached.
The rollers will be set in rotation either with muscle power and a handle or with an electric motor.
The upper rollers are used to get metall sheets, the lower ones for sticks or wire (allways in semi-square cross section). To get round or other formed wire it is necessary to use a hole iron.
It is important to anneal the material after each few passages, otherwise it gets too hard and may breake.