A MOG limiting device, herein described as a MOG limiter, approximates a portion of the curvilinear length of a concave. The MOG limiting device can include a connection point near the middle of a concave, slightly offset from center. A bolt, washer and nut assembly protrudes downwardly from the underside of the concave. Two assemblies are positioned in the middle of each side of the concave. The assemblies cooperate with a mounting plate on the MOG limiters to form an upper concave connection and a lower concave connection in each half of the concave. In the cross frame, insert slots are positioned to receive a hinge point located at the end of each arced member making up the frame (rail supports). The hinge points are slidably inserted into the opening and then rotated upwardly to be positioned adjacent to and in conformity with the curvature of the underside of the concave with the connection assemblies holding the MOG limiter in place.