often includes spraying each aluminum blank with boron nitride bn the boron nitride lubricates the interface between the blank and forming surface to facilitate metal flow over a die surface facilitate part release from a die surface and generally prevent metal workpiece to metal tool contact such coating with bn yields much better results than with un lubricated aluminum but does not avoid adhesion of some aluminum particles to the steel dies these particles lead to scratches on subsequent panels which are sanded out in an expensive metal finishing operation periodically the massive dies are removed from the press allowed to cool to room temperature then manually ground polished to remove adhering aluminum before being put back into production practices of this invention reduce the need for cooling the tools to room temperature to remove aluminum particles this increases output of formed aluminum alloy sheet metal products improves sheet metal product quality and reduces costs in one embodiment of the invention an oxidation process would involve periodically forming a bare magnesium alloy blank in a hot forming process similar to that used to the one used to hot blow form aluminum alloy panels this die surface cleaning step would be performed when it is observed that aluminum particles adhering to the hot forming tool surface are marring the surface of formed aluminum sheet metal parts the heated forming tools remain in the forming press but the delivery of aluminum sheet blanks is temporarily interrupted for this die surface cleaning procedure the adherent.