How to paint a metal garden fence?
Many have resorted to using DIY metal fence paint kits, but after spending hundreds of dollars on exterior paint, you’ll only have a couple of years of corrosion resistance.
With a little research and preparation, choosing the best method for painting your fence will ensure that your new fresh coat will last much longer than factory-painted fence panels have in the past.
DIY Metal Paint Kits are not Durable
The safest bet is to do it yourself with an exterior primer and topcoat or just topcoat/primer if you want to save money. Just know that Rustoleum won’t cut it for this project. As we mentioned before, using DIY metal fence paint kits like Rust-Oleum may be easy and inexpensive, but you’ll end up throwing money away on replacing your metal fence way sooner than you should.
Starting with bare metal, interior or exterior primer is best to protect the surface of the fence panels before applying any paint. If rust-proofing has begun to appear on the areas that are more prone to rust (where caps and posts join, for example), then it’s time to clean off this corrosion first with steel wool or sandpaper. Any loose pitting should be scraped away, too, before starting your project. Staining will help hide these imperfections later but make sure not to throw out those old rusted pieces because you may need them later on… Many DIYers find it easier at this point to remove the fence panels from their posts if possible for easy access.
Steel Woolvs Sandpaper
Using steel wool is the most efficient way to remove rust, but it’s important not to rub too hard as this will scratch the metal fence. Instead, if you’re planning on staining your panels, scrub with the grain of the metal (check out our article about painting over stains here ). Using sandpaper, though, gives you control over how much or how little rust removal you want to do because you can use finer grains for more gentle scraping. But again, make sure not to scrape too hard because this could also damage your metal fence by creating deep drilling, which will always invite corrosion under the paint in the future.
After completely removing all residue and loose pieces, attach a wire brush (self-cleaning type) or an angle grinder with a wire wheel to your drill for an efficient (and safe) way to remove any remaining rust. Be careful not to go too deep, though, or you may end up with holes that will need more filling and sanding later on. On the other hand, if you need more time before removing all corrosion, you can always use a chemical rust remover like CLR, which is acidic (vinegar-based) but less likely to cause pitting than muriatic acid cleaners. However, it’s still important to protect the surface of the metal fence with primer afterward.
Primer vs. Paint
Applying primer preps the surface of metal panels just as well as using exterior paint would, but how long they last depend on what kind of topcoat your panels will receive. For example, using an oil-based primer helps the topcoat stick to the metal panel much longer because it penetrates deeply. This is why oil-based paint will generally wear better than latex and especially better than acrylic primers. Acrylic primers, though, are by far the most common type of primer used for outdoor projects like painting fence panels, and they work great too, as long as you let them dry properly (at least 8 hours) before applying your exterior paint or topcoat.
Exterior Paint is Best
With all that rust removed and powdery residue scraped away, it’s time to apply a color that matches your taste. Using exterior paint (latex) gives you more durability than interior/exterior primer alone, becoming chalky and wearing over time. Latex will also give you more flexibility in terms of color choices. Just know that all latexes will eventually peel away from metal (especially in areas where paint is chalking), and it’s almost inevitable with regular outdoor exposure to sunlight and rain or snow. This means that painting your metal fence panels is only a short-term solution, even when using the best exterior paints like Pratt & Lambert.
But what if you absolutely don’t want to pay someone else to remove, prep, and reattach your fence panels? What if it doesn’t make financial sense, or you can’t wait for them to come back? Well, there are some other options… Simply removing the caps from your posts is one option, but this may take weeks and require much more work than you may be willing to put in for a temporary fix. Then there’s the idea of removing all your fence panels and reattaching them one by one so that they don’t break while being moved across the property or off-premises, but this takes time and patience and again doesn’t do anything for the rust.
This leaves us with using Removable Bonding Adhesive, also known as Polyurethane Glue. In fact, many professional painters use this type of glue to attach their fence panels without any screws, nails, or welding, even though it costs more upfront. The reason is that it will hold better over time (with proper preparation) than other types of adhesives like silicone which can take several coats before it sticks to the metal. But how well does polyurethane bond? For example, can you drill into it later if you want to attach your fence panels with screws or other hardware?
Well, that depends on how much polyurethane glue was applied and how long it’s been since the first coat cured (at least 24 hours), but generally speaking, you should be able to drill through wood posts without worrying about damage for many years. You may even be able to remove your cap nails or screws after a few years because the adhesive breaks down, eventually allowing the caps to twist right off.
But what about metal fence panels? Although polyurethane can hold them together securely over time, it doesn’t have nearly as much durability as Welded Wire Fencing Wire does, especially after several years of exposure to the elements. The reason is that polyurethane is water-soluble, so it won’t take much moisture (like rain) over time before it starts to lose its grip on metal fence panels.