Painting aluminum trim coil at home and in workshop Painting aluminum trim coil at home and in workshop â??Painting aluminum trim coilâ?? is often asked about since aluminum siding and trim has been applied in decoration of so many houses in the past years. Learning about painting process in the workshop helps you to fully understand steps you should do at home to repair items made of trim aluminum coil. Before getting an aluminum trim coil roll painted, manufacturers would first clean the roll surface completely, either in physical or chemical ways. Sometimes mechanical equipment is necessary, too. The purpose is to remove any materials that might prevent the following anodizing step from going on effectively. A completely cleaned surface of aluminium coil will obtain a thick condense layer of anodizing film on the surface, but there will be micro holes on the surface, which should be concealed to make the film stronger and harder. To paint the coil, pvdf, pe and pvc paints are all applicable. These paints are divided into primers and finishing coats. Multiple painting produces lasting color coated aluminum coil in severe natural conditions. If you need to paint aluminum trim coil at home, the steps are similar in exception to the anodizing part. You should first scrub the aluminum part to be painted with soapy water by combining 1 gallon of warm water and 1/4 cup of dish soap in a bucket. Then then scrub down the entire aluminum surface to remove dirt and residue with the brush soaked with soapy water. Wipe the aluminum with a clean, damp cloth, and if there are still residues on the aluminium surface, brush it again until it gets fully cleaned. After the surface gets dry, you should begin your painting. Now the point is, do you need a primer? If you want your paint work last as long as possible, the answer is yes, for a primer functions as a secondary protection line of the aluminium trim coil. Make sure the primer you choose is safe for use on aluminum. Do not move on the next step until the primer is dry. Then dip a paintbrush into the paint, and brush the paint onto the aluminum using long, even strokes. Never allow anyone touch the aluminium until the paint gets dry.