An apparatus for spreading liquid liner in the interior of a rocket motor tube, the rocket motor tube having masks attached at both ends of the rocket motor tube, the apparatus including a generally vertical support plate with an opening there through; a flange with a center opening attached to the support plate; a support tube inserted into the center opening of the flange; a stop disposed in the support tube, the stop abutting the support plate and engaging a mask on one end of the rocket motor tube; a retaining funnel that engages a mask on the other end of the rocket motor tube; a retaining ring that threadingly engages the retaining funnel; and at least two clamps attached to the support tube and engaging the retaining ring.