Pre-formed plug with inter-blade profiles for hydraulic turbines

An inter-blade profile for a turbine runner blade, wherein said inter-blade profile is configured to extend transversely from a turbine runner blade in a water turbine, said inter-blade profile comprising a profile component extending transversely from a plug, the plug forming a base for said profile configured to be inserted into a corresponding hole made in a side wall of said turbine runner blade, the plug comprising an upper side that extends completely around and outwardly beyond said profile and lateral walls such that, when inserted into the hole in the turbine runner blade, the upper side is exposed and flush with the side wall of the turbine runner blade and the lateral walls extend into the turbine runner blade, and the profile extends from the exposed upper side of the plug, and wherein the plug is a separate component from the profile component and joined to a lower part of the profile component.