Maintaining Iron Antiques
by Bob Brooke

Wood and iron were the two most common materials used to make everyday objects in the 18th and 19th centuries. Blacksmiths turned wrought iron—grainier than cast iron and usually marked by the forge—into tools, weather-vanes, fireplace accessories, trivets, and keys. Ironmakers produced cast iron—harder and more brittle but with a smoother surface—as early as the 14th century, but it wasn't until the mid 19th century that it became the virtually universal replacement for wrought iron. Cast iron, too, was made into the full gamut of objects from furniture to cooking pots to toothpick holders.

In order to make sure antique iron objects stand the test of time, it’s necessary to clean and protect them.

How to Clean Rusted Iron
Rust is the major enemy of iron and, and though slow, it’s extremely sure. Unchecked, rust will eat away until the entire object disintegrates. Low humidity will usually stabilize the rust so that corrosion isn't active and no further destruction takes place. So you have a choice. If you think polishing will only emphasize an eroded surface, you can leave the rust and treat the object to prevent further damage, or you can clean it back to a proximity of its original state. The decision is up to you.

Here are the usual steps to clean iron or steel:

1.Wash with warm water and a little mild detergent.

2.Scrub with kerosene or turpentine to remove any oils or grease.

3.Polish with steel wool or aluminum oxide paper (Tri-M-ite), using grits of 600 or 400. If you want to remove rust, you can combine a commercial rust-removing liquid with this step (be sure to wear rubber gloves or your hands will be a mess).

4. Rinse thoroughly, dry with a cloth, then let sit in your oven at lowest heat (not more than 200 F.) for an hour or so to dry out completely.

Other Rust Removers
Baking soda, vinegar, citric acid, lemon, and salt are good cleaners for a variety of rusted conditions.

Baking soda works best on severe rust. When using it, rinse the object and shake it dry. Dust it with baking soda, which will adhere to the damp areas. Make sure you cover all rusty areas. Leave the item for an hour or so, then scour it with steel wool or a metal brush, removing the rust down to the metal. Rinse, and towel dry. Be aware that it can take up to an hour before you can really start to work away the rust. Be prepared to use some elbow grease.

Vinegar works best on significant rust found on tools and on objects that can be submerged without compromising the integrity of other surfaces. Submerge your object in white vinegar and let it sit overnight. Remove it from the vinegar and scrape it with a metal brush or steel wool. If your item can’t be submerged, soak rags in white vinegar and wrap the rusted area.
This “let sit and forget” method is easy and takes hardly any elbow grease to work away the rust once you remove item from the vinegar.

Citric acid works similar to vinegar. While you may not have this lying around the house, you can easily find it at most health food stores. Add a few inches of hot water to a bowl and sprinkle in two to three tablespoons of the citric acid. Submerge your object and let it sit overnight. In the morning, remove it and scrub off lingering rust flecks with a brush, rinse, and pat dry. This is an alternative “let sit and forget” method.

For less stubborn rust stains, or on objects such as kitchen utensils that may have a little rust here and there, salt and lemon work well. Generously coat the rusted area in a layer of salt, cut a lemon in half and squeeze the juice over the salt. Let the mixture sit, then scrub away the rust with the rind. If rust remains, repeat the procedure and let the salt and juice sit for another hour or two, until rust disappears completely. Rinse, then pat dry.

Protecting Cleaned Iron Objects
Never use linseed oil on iron, because it polymerizes and creates a hard surface that’s virtually impossible to remove. The best protective agent is hard paste wax or shoe polish. Some polishes contain water and tannic acid, so check the label to avoid these. Use a clear shoe polish or a car wax, let dry for a few minutes before polishing, wipe thoroughly and apply two or three times to build up a good, hard coat. Once you complete this treatment, you’ll need to do little more than dust. Unfortunately, this will protect your piece but eventually soften. It's just like a shoe shine good for a day unless you walk through water.

To keep your iron objects from rusting again, you’ll need to keep them in a low humidity environment. Summer is often damp in many places due to rains, so it’s important to be particularly vigilant then.

Any of the old-fashioned stove polishes, consisting of black graphite with petroleum oil, will add color and a pleasant sheen. If you use black shoe polish or wax, the effect will initially be the same, but the surface may soon take on an undesirable look of having been painted.

If you live in a humid climate, an air conditioner or a dehumidifier is a worthwhile investment to help keep iron from corroding. White cotton gloves will also help you to protect polished iron from your moist fingerprints.

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