A method includes forming a sheet of material having first, second, third, and fourth ends. The third and fourth ends extend longitudinally between the first and second ends. First and second protrusions are formed at the first end. The first and second protrusions extend longitudinally outwardly from an edge of the first end. The third and fourth ends are coupled to one another to create a longitudinally extending compressor shell having a stepped region at the edge of the first end where the third and fourth ends meet.