Abstract: A thermal strip chart recorder is provided in which the strip chart is transported at a precise predetermined speed with consistent print darkness. A thermal printing assembly compresses the chart against a cushioned roller with sufficient force to provide dark printing. The printing assembly includes a plurality of printing heads mounted for independent movement in a side-by-side relationship. The roller includes circumferentially spaced sprockets near either end and a central, coaxial, cushioned sleeve which rotates freely with respect to the sprockets. In operation, the roller is driven at a precise rotational speed and moves the strip chart at a precise linear speed by means of the sprockets, which engage sprocket holes in the strip chart. In operation, the strip chart is moved at a precise speed regardless of the printing head pressure, because the freely rotatable sleeve exerts no drag on the strip chart regardless of how much the sleeve is compressed.