Rotary bell cup atomizing apparatus is provided having a rotatable bell cup driven by a motor shaft dimensioned so as to provide an annular gap between the outer, rear surface of the cup and the shaft extending an effective distance axially adjacent the shaft. Solvent channels extend within the assembly circumventing the gap and discharge into the gap. During cleaning of the atomizer, solvent passes partially through the paint nozzle and partially through the solvent channels impinging directly upon the shaft, then migrating over the outer surface of the cup. The inner and outer surfaces of the bell cup and the motor shaft are simultaneously cleaned. A replaceable sleeve placed inside the cup adjacent the front surface thereof absorbs the force of paint impinging thereon. The cup may have at least one balancing indentation immediately adjacent the sleeve.