In order to ensure a solid bond between the sprayed coating and the base material to which it is applied, the areas to be metalized and the adjacent areas must be free from such contaminants as oil, grease, water, paint, and other foreign matter.  To thoroughly clean these surfaces, a suitable chemical solvent (or heat) and wire brushing (or sandblasting) must be used. If the surface to be metalized is of a porous material, it must be heated sufficiently to drive out any oil or other contaminant.  Generally a temperature of 400 to 500° F is satisfactory.  (For some surfaces, a chemical cleaning may be necessary before heating.)  Carbon formed by the heating operation may be removed from the surface by sandblasting.  The final cleaning is accomplished by applying the chemical cleaning solvent with a clean brush.
