A coating apparatus has compact coating assembly modules which require less storage space and are easier to handle and which through the common use of parts and accessory tools provide a reduced manufacturing cost of the apparatus as a whole. A coating assembly which rotates during coating and a coating assembly which does not rotate during coating can be interchangeably installed to a support frame. Two bearing cases are mounted on the support frame, and the coating assemblies each have two shaft parts which can be removably set in the bearing cases. The shaft parts of the rotating coating assembly can be rotatably set in the bearing cases, and a shaft part of the non-rotating coating assembly can, when set in its corresponding bearing case, be anchored to a fixed part so that it cannot rotate. Another coating assembly which does not rotate during coating has left and right mounting parts which can be removably fixed to bearing cradle parts of the bearing cases.