An apparatus for maintaining uniform tension across a width of a web including a frame, a roller, a shaft about which the roller rotates, a first arm rigidly connected to a first end of the shaft, a second arm pivotally connected to a second end of the shaft, and a third arm rigidly connected to the second end of the shaft. The first arm is pivotally connected to the frame by a first joint. The second arm is pivotally connected to the shaft by a second joint and to the frame by a third joint. The third arm is coupled to the frame through a fourth joint. The first, third, and fourth joints are offset from the axis of the shaft by substantially the same distance. The first and third joints are offset in the same direction. The fourth joint is offset in the opposite direction.