A levelling machine includes a pair of spaced apart rail assemblies, a gantry assembly and a face mill assembly. The spaced apart rail assemblies define an x axis. The gantry assembly is moveably attached to the pair of spaced apart rail assemblies whereby the gantry assembly defines a y axis. The gantry assembly is moveable in the x axis along the pair of spaced apart rail assemblies. The face mill assembly is moveably attached to the gantry assembly and is moveable in the y axis along the gantry assembly. The face mill assembly has a plurality of saw blades, the saw blades being generally in an x-y plane defined by the x axis and y axis. The saw blades have a plurality of teeth that extend downwardly generally in a z axis. The face mill assembly is moveable in the z axis.