The Surface Preparation – First, clean the dirt, grease, & contaminants with a degreasing solvent. Then deburr with abrasives or wire brushes. Finally, remove weld discoloration via grinding & pickling paste. Choosing the Right Abrasive – Coated abrasives: Smoothing edges. Non-woven: Finishing & blending. Scotch-Brite: Brushed finish.