A magnetic drum separator is provided. The drum separator includes a drum and a pulley arrangement that rotates the drum. The drum separator includes an end plate coupled to the drive assembly, and the drive assembly rotates the end plate with the drum. The end plate includes a radially oriented slot. A plurality of magnets is disposed in the drum, and the magnets are attached to the end plates and rotatable with the drum. A cam assembly is disposed in the drum and remains stationary during rotation of the drum. The cam assembly includes a cam with a cam track formed therein. The magnets have a cam follower located in the cam track and an end plate follower located in the slot of the end plate. The cam track and the radially oriented slot guide the plurality of magnets to move radially inwards and outwards as the magnets rotate.