Abstract: A device is provided for producing a large number of fibres, generally from a thin wire, in which a cutting mechanism imparts a high initial speed to the cut wire lengths, which are then oriented in the same alignment by being passed through a funnel-shaped opening into a pipe whose diameter is less than the length of the fibres; a method is provided for using the thin oriented and aligned fibres to bond and reinforce materials, for example, concrete, and to manufacture sandwich panels, in which the concrete is applied to the fibres shot into the sandwich panels in accordance with.