Coating metal surfaces

If you’ve ever wondered about refurbishing a metal object, or about painting metal surfaces in general, this is completely doable using metal primer. It’s also fairly easy to accomplish! Even better, metal surfaces of repurposed objects do not require you to maintain the previous paint color, which can open the door to all sorts of interesting projects. As long as you prepare your metal properly before applying the paint, you will be able to complete this task easily.

Work in a ventilated area. Working around paint and rust particles can be harmful, so choose a well ventilated area where you can put a drop sheet down underneath your metal project. Wear gloves and a dust mask while you work.

  • Keep a damp cloth nearby to wipe away paint, dust and rust particles periodically while you work. This is much safer for you than waiting until the end to deal with them.
  • If there is any chance the paint you are stripping may contain lead, the dust mask is an absolute must for your own safety.

Remove the old paint from the surface. Use a wire brush to strip the paint from the metal, remembering to wipe dust and paint particles away with a damp cloth as you work.[1] If you prefer, you can use sandpaper to remove the paint.

  • A combination approach is best – stripping large surfaces will go much faster with a wire brush, and then use the sandpaper to get in the nooks and crannies.
  • A cordless drill with a wire brush attachment is also an option, and a good one if you are stripping away paint from a large surface area. Remember to wear protective ear muffs when operating drills.

Clean the surface of the metal. Wipe away all paint dust with a damp cloth and discard the cloth. Scrape off any hunks of remaining paint. Use a fresh cloth to give your metal a thorough rub down, cleaning off all loose paint, dirt, grease and grime from the surface.

  • Even if the surface looks fairly clean, don’t skip this step. You want the surface of the metal to be virtually spotless, or as close as you can get to it.
  • Failure to clean your metal properly will result in a lousy paint job. The paint won’t stick to the metal properly and will peel off easily.
  • Oils on the surface of new galvanized metal, which may or may not be visible to the naked eye, can hinder your paint job if they aren’t removed. Use a simple detergent solution to wipe down new galvanized metal.

Sand down the metal until it is as smooth as possible. This will ensure that you get the longest life out of your paint job. After sanding, wipe down your metal one final time with a damp cloth to remove any lingering debris.

Apply a zinc-chromate primer first if the metal is rusted. You will want to do this before you put on the regular primer, but only if you are working with rusted metal. If your metal isn’t rusted, start with the usual oil-based primer that is described below. Before application, scrape off any loose rust and wipe it down to remove any flakes or residue. Once the rust is removed, coat the metal with zinc-chromate primer before using a full-bodied primer.

  • You will need to prime your surface with the full-bodied primer immediately after you use one of these products, so don’t apply them until you are ready to prime.
  • Zinc-chromate is a corrosive resistant substance. You spray it on first because you want it to be closest to the surface of the metal, to protect it from rust. After applying this substance, you should immediately apply the regular “full-bodied” primer so that the zinc-chromate remains as the first layer. It also acts as an adhesive for the full-bodied primer.

Choose an oil-based primer. Make sure your primer and your paint are compatible with one another.  Look for primer products that are made specifically for metal, as well, since these will best adhere to the surface.

  • Most primers come in a spray can for ease of use, but if you prefer to use a brush to apply it, metal primer also comes in a bucket or can for that purpose.
  • Primer prepares your surface so that the paint will adhere well, but it also helps to smooth out any color and texture that you weren’t able to remove from it.

Paint the surface. Make sure not to apply thick coats, it is much better to apply multiple thin coats.