Disclosed herein is a tool for holding a spray painting instrument, such as a painting gun for painting an internal surface of a pipe. In particular, the inventive tool is ideal for painting the interior of curves and angles in a pipe and is capable of moving through and uniformly painting up to 90 degree angles of pipes or hollow tubes. The tool has a hollow central tube for carrying a spray-painting gun and at least two projections extending outwardly from an outer surface of the hollow tube. A retracting arm assembly is provided on each projection. Each retracting arm assembly includes first and second retracting arms and a corresponding force exertion mechanism. In operation, when the tool is inserted inside the pipe, each retracting arm touches the internal surface of the pipe due to an outward force exerted thereon. The tool is movable inside the pipe and adjusts automatically to different pipe diameters. The tool can be used manually or in an automated fashion to push and pull the paint gun and paint the interior of a pipe.