Preventing Grills and Patio Furniture from Rusting
Barbecues, patio furniture, handrails, lawn and garden equipment, steel window frames, rain gutters, and downspouts are all susceptible to damage by rust. Aside from its ugly appearance, untreated rust can lead to other damage.
A rain gutter with a rusted joint, for example, can leak and allow water to travel along the wood trim at the roofline, or, perhaps down the wood siding, ultimately resulting in rot, which can cost a pretty penny to repair. Rust also presents a safety issue. A rusted-out screw in a handrail or the rust-ravaged leg of a garden chair could send an unsuspecting guest on a nasty fall. Rusty outdoor power equipment leaves the operator particularly vulnerable because a rusted bolt could act as a projectile.
Paint and oil are two types of coatings that you can rely on to shield a metal surface, and, therefore, prevent oxygen and water from doing their damage.
A good paint job always begins with a high-quality primer. In this case, the primer should be made specifically for metal. Certain pigments contained in paint, such as zinc and iron oxide, adhere to metal much more effectively than other types. Whichever primer you decide to use, choose a topcoat that is compatible with the primer. In general, an oil-based finish coat is the most compatible with an oil-based primer. It also offers the greatest abrasion and weather resistance.
There are, of course, exceptions to the oil-based topcoat rule: For example, you should consider the architecture of gutters and downspouts. A flat-luster, acrylic, water-based topcoat produces a low sheen that tends to hide certain flaws, such as dents and joints. Plus, due to the inaccessibility of gutters and downspouts, more abrasion-resistant oil-based paint becomes unnecessary.
Grills, fireplaces, wood or coal stoves, heaters, and furnaces generate heat that exceeds 200 degrees. They should be topcoated with high-heat enamel paint specifically designed for use with items that are too hot to touch. (Note that most paints emit a harmless odor the first time they’re heated.)
One coat each of a high-quality primer and a high-quality oil-based topcoat is all that should be required. You can apply the primer and topcoat using a brush, roller, paint pad, or sprayer.
When brushing an oil-based paint, use a natural-bristle brush. Synthetic brushes made from nylon or polyester work well with latex paints. However, they’re too stiff for use with oil-based paints, often causing brush marks — not to mention loose bristles — to remain in the finished product.
Spray painting using canned aerosol spray paint or a do-it-yourself spray rig poses several advantages. Spray-painting works well on intricate designs and is smoother (without brush marks). You need to take several precautions when spray-painting:
Be sure to wear eye protection and a respirator. And never spray-paint in an area where flames or sparks could ignite volatile vapors.
Mask off surrounding areas with plastic, paper, or canvas to avoid damage by overspray. Don’t try spray-painting on a windy day unless, of course, your neighbor’s car needs a paint job.
If you’re using a spray rig, use a tip that’s compatible with the paint to avoid putting too much paint on at once. Tip sizes vary in accordance with the type of paint being used (oil-based, water-based, lacquer, and so on).
Avoid paint runs by applying several thin coats rather than one heavy one.
Protecting your metal with paint helps prevent rust as much as it can be prevented. However, as paint is chipped or scratched, and as it oxidizes with time and the elements, its effectiveness as a rust barrier diminishes. Eventually, moisture can make its way through the paint to the metal’s surface, and rust results. To extend the life of your paint job and your ornamental iron, touch up chipped and scratched areas immediately.