At least one yarn is arranged helically about at least two conveyor portions, thereby providing a weft having a first weft portion having yarns arranged at an angle, θ, with respect to the conveying direction of the conveyor portions, and a second weft portion having yarns arranged at an angle, −θ, with respect to the conveying direction of the conveyor portions. Center sections of the first weft portion and the second weft portion are then fixated to each other, e.g. by stitching and/or by applying a resin to the center sections. Side portions of the weft are then cut, thereby separating the first weft portion from the second weft portion. Finally, rim sections of the first weft portion are fixated to rim sections of the second weft portion, e.g. by stitching and/or by applying a resin to the rim sections.