A slot drum for a winding machine for traversing a yarn has a drum body including a first half and an adjacent second half, the drum body held in a rotationally fixed manner on a drum shaft. The adjacent first and second halves defining a yarn guide slot that extends around the drum body. The first and second halves include a side shield, a cylindrical jacket, and a hub for mounting on the drum shaft. The first half is displaceable on the drum shaft in a direction of the drum axis via an actuator. The first half rotates relative to the second half as the first half moves in the direction of the drum axis.