Abstract: A mechanism to be utilized for winding wire on a spool in tight coils without space between them. The mechanism includes rotating devices (14) and (16) which when activated rotate the spool (12) about its longitudinal axis (13). A wire guiding unit is arranged to be automatically moveable in all directions to the side of the thus rotating spool. The unit comprises a pressure roller (2) or equivalent which with a predetermined force presses that section of wire which during winding runs inwards at an angle against that section of wire which comprises the previous coil of wire in the layer being wound. During winding the pressure roller (2) adjoins and presses the section of wire being wound against the last wound coil of wire and the mantle surface of the spool or the already wound underlying layer of wire.