An apparatus (un-interleaver) for unwinding a roll of material interleaved with another material, and for separating the materials, includes a first platform, a second platform, a tension-sensor, an edge-sensor, and a controller. The controller monitors signals generated by the tension-sensor and the edge-sensor, and in response to the signals: a) causes the speed at which the second platform rotates to change to maintain a predetermined tension in the second material as the second material travels from the first platform toward the second platform, and b) causes the second platform to move relative to the first platform to align the edge of the second material traveling toward the roll of second material with the edge of the second material in the roll.