Abstract: A method of and device for producing rolls of web material, especially self-supporting material such as sheet metal, in a continuous process which is divided into timewise and locally separated on-winding and winding-up phases. The on-winding is effected automatically in a space or chamber corresponding in shape to the shape of the desired initial roll to be produced. This on-winding is carried out on mandrels extending from opposite sides into the above mentioned space or chamber. When the initial roll of web material has been prepared, the latter is conveyed by the mandrels to a winding-up station. Here, the mandrels are withdrawn from the roll prepared so far and returned to the on-winding station for producing another initial roll, and further layers of web material at the winding-up station are wound up and around the initial roll of web material by feeding web material to the winding-up station, until the roll has reached its desired diameter.