Method and apparatus for friction-based repair of leak paths in die-cast parts

A method of repairing a leak path formed through a casting defect in a die-cast part, the method comprising:

• inserting a plug into first threads of a bore formed in a die-cast part having a casting defect, the bore being adjacent and connected to the casting defect, and a leak path being formed from the bore through the casting defect;
• pilot drilling the plug within the bore to leave a shell of donor material around a wall of the bore;
• and
• operating a mechanical bit within the bore and through the shell of donor material to generate plasticized local material along an inner surface of the bore wherein the plasticized local material flows into the casting defect to seal the leak path, and the plasticized material produces a clean, sealed hole that is ready for tapping and that includes a plasticized layer along the inner surface within the bore.