A modular bottom shell of a multi-shell crusher device, the shell includes a central hub having a centered cylindrical support hole and at least two support arms extending orthogonally from the centered cylindrical support hole, each support arm having an end plate, and wherein at least one of the two support arms has an orthogonal bore therein which extends from within the centered cylindrical support hole to an outer portion of the support arm; and at least two outer shell sections having an annular inner surface, and wherein each of the outer shell sections has an upper surface and a lower surface, the upper and lower surfaces extending from one end of the outer shell section to the other end of the outer shell, and a first vertical end plate on one end of the outer shell section and a second vertical end plate on the other end of the outer shell section, and wherein each vertical end plate has at least one bore therein, which has a corresponding bore within one of the end plates of the support arm.