To provide a molding frame capable of holding a plane element in an approximately U-shaped molding acceptor, forming one U-shaped leg of the molding acceptor as a stopper leg to the plane element, forming the other U-shaped leg approximately parallel to the stopper leg as a thrust leg for tight fastening the plane element between both legs and facilitating the built-up thereof with high stability at a low manufacturing cost.

The thrust leg has both clamp and objective deformation areas, and the clamp area can be pushed against the plane element under the deformation in the objective deformation area.