Putting Rust to Sleep

When it comes to your car, winter sucks. Its extremes of temperature, combined with snow, ice and road salt, can have devastating effects on a vehicle's exterior and suspension. As car aficionados begin to prepare their collector cars for winter storage, many are seeking better ways than simply putting their cherished wheels under a fabric car cover. Now there is a portable, controlled-environment storage system that is available in America after extensive use in Britain. Its goal is to protect the vehicle and keep rust at bay, and while traditional covers can do the former, they are often not too good at the latter.

"Rust starts when iron and oxygen combine in the presence of water," said Graham Horder, managing director of Airflow, the parent company of Air Chamber USA. "When water comes in contact with iron, it combines with the oxygen in the air to form a weak acid called ferrous oxide or that reddish brown rust. And because rust's molecules are larger than those of steel, it grows inwardly, eventually pervading the thickness of a vehicle, degrading its structural integrity and flaking into rust."

To prevent rust from forming, it is critical to eliminate a vehicle's exposure to water, which is not that easy. From washings to exposure to the natural elements, water is all around. More insidiously, water occurs in normal air as water vapor. The rate of transformation of vapor to liquid water depends on the temperature of the air.

"The amount of water vapor that air can contain at 90øF is twice that at 70øF," noted Horder. "When air cools, water turns into condensation. That moisture will form on any car in a garage, unless it (the garage) is permanently heated to the same temperature as the air outside. And condensation occurs in every cranny."

A heated, well sealed-garage is often considered to be the safest method of preventing condensation, but they're expensive to build, maintain and operate. And garages can actually promote condensation.

"Imagine a perfect winter's day with dry roads and crisp, blue skies," Horder said. "While enjoying a brisk drive, the engine compartment and most of the interior will heat up; the rest of the chassis and sheet metal will cool to air temperature. However, shortly after returning to a warm garage, condensation will set in and rust begins its destructive process."

The solution is to create a sealed environment and draw out the moisture as well as dust. Air Chamber, a cross between a tent, a transparent car cover and a portable garage, is based on that principle. It is a significant departure from traditional auto covers that lie on top of vehicles, potentially leaving scratches and marring paint finishes. An inner semi-rigid frame allows the chamber to stand up, and, once in place, a collector car can enter and exit with ease. No portion of the Air Chamber touches the car and small fans blow ambient air into it, which supplies a constantly moving airflow. In addition to guarding against rust, this also prevents other types of winter storage damage like mildew, which can form when fabric and leather get damp in stagnant air. An Air Chamber typically operates for only around $50 per year.

"It's tempting to put your head in the snow and think that winter can't get your vehicle because the last restoration was so good that rust can't happen," Horder said. "Body shops will love you for it. After all, they know those delicate snowflakes can eventually lead to a new kind of flaking on your collector car."

Driving Today Contributing Editor Tom Ripley writes about the auto industry, bad weather and the human condition from his home in Villeperce, France.