A dowel hole and slot cutter comprise a motor having a base slidably mounted on a track and a cylindrical cutting bit mounted at one end of the motor and extending outwardly therefrom. The turbulator also includes a plurality of louvers spaced along the base and extending longitudinally and generally perpendicular to the base in an alternating manner, the louvers being rolled in a direction parallel to a longitudinal axis of the strip. A variable speed electric motor is disposed in the housing and includes a shaft which extends forwardly in a direction parallel with a mounting portion of the longitudinal member. Heat is then applied to the filler material and across the repair opening to melt the filler material, which is allowed to cool to form a repair deposit fused to the substrate and across the opening. The sleeve is disposed within the housing.