OAR 740-105-0160: Preparation of Base Metals

(1) Thermally shaped surfaces including repair cavities shall be ground lightly to remove residual material (approximately 1/32 inch) from the surface to be welded. (2) Surfaces to be welded shall be free from the following: (a) Fins, tears, cracks, torch gouges, excessive surface irregularities, etc. (b) Loose or thick scale, slag, rust, moisture, paint, grease, and oil or other foreign materials that may be detrimental to the weld.