A tool for assembly of an inner enclosure of a generator or a machine comprises a first part and a second part. The first part comprises a plate with one edge constructed to form a first half-ring. The second part comprises a second half-ring corresponding to the first half-ring of the first part. Upon assembly of the first part and the second part, the first half-ring and the second half-ring form a full-ring to encompass a shaft of the generator or the machine and to connect to an inner enclosure of the generator or the machine.