In the texturing unit of this invention a data storage disk is gripped between a pair of opposed, counter-rotating cylindrical abrasive mandrels, which are covered with soft, porous pads. The frictional force between the disk and the pads raises the edge of the disk against a pair of driven rollers which impart a rotational motion to the disk. A texture pattern of uniform grooves, having controlled peak heights and valley depths, is formed simultaneously on both sides of the disk. A system for delivering an abrasive slurry to the pads includes a closed loop in which the slurry is recirculated and a dispense section of that loop, from which a blast of pressurized air periodically expels the slurry through applicators and onto the pads. The continuous recirculation of the slurry prevents settling.A unique feature is that the groove length may be controlled by adjusting the ratio between the rotational speeds of the disk and mandrels. The groove pattern is primarily circular but a radial component may be added by varying the position at which the pads contact the surfaces of the disk.