Controlling Rust

In your experience you may have debated whether to purchase a product made of steel which is strong, solid and durable, or to go with something made of a lighter material that is easier to maintain, such as plastic. Fact is, products made of steel when properly maintained will far outlast most other building materials.

In your experience you may have debated whether to purchase a product made of steel which is strong, solid and durable, or to go with something made of a lighter material that is easier to maintain, such as plastic. Fact is, products made of steel when properly maintained will far outlast most other building materials.

With steel, rust eventually will set in, but that really isn't so bad. Some of the oldest standing American structures were built from steel and continue to stand tall and majestic after decades. Can you imagine how long the Manhattan Bridge or the Golden Gate Bridge would have lasted if they had been made from wood or plastic?

What's the secret of keeping steel in good condition? A reasonable maintenance program. The Golden Gate Bridge in San Francisco is constantly being cleaned and repainted. A bridge of steel built over salt water is a world-class maintenance challenge.

Sooner or later everything oxidizes in one way or another. Steel rusts, paint chalks and plastic gets brittle. When plastic gives off enough free chlorides (which it does from the day it is made), the result is a brittle material that cracks easily. Oxidized plastic cannot be repaired, so we recommend contributing the crumbling goods to a recycle center or, better yet, a charity.

When paint mixes with oxygen, it gets chalky. Paint is not normally very thick, so after polishing away a chalky surface several times, most paint begins to fade and finally disappear. When steel oxidizes, the result is rust. But unlike plastic and paint, rust can be removed from steel year after year, layer after layer, without causing appreciable damage to the structural value of the steel. This is probably the main reason why steel is such a good buy. Simply put, steel can be maintained over very long periods of time. All you have to do is control its rusting.

You can't prevent rust, but we can show you how to slow it down. Paint and oil are two types of coatings that can be relied upon to shield a metal surface and therefore prevent oxygen from getting to it. On wood, paint keeps water from causing rot. On steel, the same paint prevents water from causing rust. As paint deteriorates (oxidizes) its effectiveness as a rust barrier diminishes. Eventually, moisture makes its way through the surface of the paint and gets to the metal. The result is rust.

Once rust occurs, it must be completely removed before a new layer of paint protection can be applied. A rust-removing chemical such as Naval Jelly works wonders on thinner layers of rust, but other techniques must be used on thicker ones. Massive layers of rust should be scraped, wire-brushed, wire-wheeled, sanded or rubbed with steel wool, depending on the density of the rust. Then, Naval Jelly should be used.

We prefer a wire wheel attached to an electric drill. With this technique, the drill does most of the hard work. Naval jelly is used to remove the really fine layer of rust that is left behind by the wire wheel. Naval Jelly is nothing more than phosphoric acid (usually found in a gelatin-like form). Phosphoric acid makes easy work of lighter layers of rust, but does not work well on heavy build-ups. Naval Jelly also is available in spray form. Whether spray or jelly, you don't want to get it on your skin or in your eyes. If you decide to use it, make sure to heed the manufacturer's safety instructions.

Once the Naval Jelly has done its job, the cleaned surface can be washed with a paste of baking soda, which, in turn, can be rinsed with water. Quick thorough drying is a must. Raw, wet steel will begin to rust in minutes.

Finally, don't rely on penetrating oil. It will break down a certain amount of rust, but it is not considered a good rust remover.

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