How to paint metal railings and gates

Video by Rust-Oleum UK. This guide is based on the "How to paint a rusty gate" video from the official Rust-Oleum UK channel. Rust-Oleum are well known for their metal paint and rust treatment products, and this video walks through the process from preparation through to the finished topcoat in clear, practical terms. Worth watching before you start to see how they handle the fiddly spindle sections.

1. Remove loose rust and flaking paint

Use a wire brush or wire wheel attachment on a drill to remove as much loose rust and flaking old paint as you can. You do not need to get back to bare metal everywhere — just remove anything that is not firmly adhered to the surface.

Work carefully around welds and joints, where rust tends to be worst. A hand wire brush gets into those spots better than a wheel. Wear eye protection throughout — flakes of rust and old paint at head height have a reliable way of landing exactly where you do not want them.

2. Sand back any remaining tight rust

After wire brushing, sand the areas with 80-grit sandpaper to knock back any remaining tight rust spots and give the primer a surface to key to. You are not trying to make it smooth — just remove the rough, powdery material and create a slightly textured surface.

On decorative ironwork with lots of intricate detail, a folded piece of sandpaper or a small flap disc on a multi-tool gets into the curves and spindles more effectively than trying to force a larger tool into a tight space.

3. Degrease the surface

Wipe the whole surface down with a degreaser or a cloth dampened with white spirit. Old iron railings and gates often have a residue of previous paint, oil, and general grime that stops primer adhering properly, even after sanding.

Let it dry fully before moving on. Painting over a damp surface is a reliable way to get a finish that lifts within weeks.

4. Apply a rust-inhibiting primer

Use a primer specifically formulated for metal — ideally one that contains a rust inhibitor. Apply it to the whole surface, working systematically so you do not miss sections. A small brush works best on spindles and intricate work. A wider brush speeds up the flat sections.

Some modern metal paints advertise themselves as direct-to-rust with no separate primer needed. To be fair, these work well on light surface rust. For anything with significant corrosion, a proper primer stage gives a more reliable long-term result.

5. Apply the topcoat in thin layers

Apply the topcoat in thin, even coats rather than one thick one. Thick paint on metal sags, runs, and takes much longer to cure properly — and on intricate ironwork, runs are very obvious once dry.

Two thin coats give a far better finish than one thick coat. Allow the first coat to dry to the touch before adding the second. Most exterior metal paints are touch-dry within an hour in reasonable weather, but check the label for recoat times.

6. Work methodically on complex sections

On gate frames and railings with multiple vertical bars, work from the inside out and top to bottom. Paint the joints and hard-to-reach sections first with a small brush, then come back with a wider brush for the accessible flat sections. That way you are not trying to dodge wet paint to get into tight corners.

Mind you — drips happen on metal painting almost inevitably. Keep a small brush handy to work any runs out before they dry. A run that dries hard on a black railing is visible from the street.

7. Leave adequate drying time before use

Even when the surface feels dry to the touch, metal paint needs time to harden fully. Most exterior metal paints reach full hardness after 24–48 hours. Avoid anything touching the surface — gates swinging against stop posts, for example — until the paint has hardened properly.

Once it has, a good result should hold for several years before needing more than a light sanding and a fresh coat of topcoat — no stripping back to bare metal each time.

When to call a handyman

Call Richard if the rust is very heavy, the metalwork needs straightening or rewelding before painting, or if the job is simply too large or awkward to tackle yourself. Front railings and gates are highly visible and worth getting right.