Before weaving, the warp yarns should first be wound in desired number and length on a so-called warp beam.
Making a warp is done in two steps. First, the desired number of warp yarns are wound onto a drum to the desired length using a so-called sectional warping machine or cone warping machine (Figure below). Next, the yarns are rewound full-width onto the warp beam of the loom.
The warp yarn should be sufficiently strong and smooth to weave without difficulty. If the yarn is too fluffy or weak for the desired weave, the warp of the loom is sized with sizing agents. These are removed again after weaving, called desizing (ยง7.4.4). Wet-spun hemp yarns do not require sizing.
Next, the warp yarns have to be inserted through healds or heddles into 2 or more shafts. This is done according to a predetermined pattern. Finally, the warp yarns have to be threaded through a reed of the loom. This reed is an elongated frame and serves to keep the warp yarns parallel, to guide the weft rapier and to strike the applied weft.