Buying guide for Best rust prevention sprays
Rust can be a vehicle’s worst enemy. It has the potential to affect nearly every part of a car, killing its resale price, ruining parts, and even causing accidents and breakdowns. This is particularly true in northern climates where salt is liberally used to keep winter roads passable.
One way to tackle rust on your vehicle is with a rust prevention spray. These sprays can help immunize your vehicle’s body against rust or work to remove rust once it has set in. Rust prevention spray is a low-cost way to save you big money in rust repair bills down the road.
Key considerations
Type of spray
When selecting a rust prevention spray, you will actually be choosing from a variety of different product types. Some are used together to treat rust, and some contain a mix of rust fighters. Common types of spray include the following.
Rust inhibitor: If you seek to ward off rust before it even starts, try a rust inhibitor. Inhibitors prevent surface rust from forming by slowing the oxidation process. This type of rust prevention spray is particularly useful in humid climates.
Rust primer: Rust primer is used as a base coat and helps bind paint to a surface. Primer is also used to prevent rust from forming.
Rust remover: If you’re already experiencing rust, you need a different type of rust prevention spray. A common method of dealing with existing rust is rust remover. Rust remover is sprayed directly onto the rusting surface, where it binds to the rust. Once it has bonded, both the rust and the spray can be washed off with soapy water.
Rust converter: Another type of spray you can use after rust has formed is rust converter. Like rust remover, it is also sprayed directly onto the rust. There, it forms a dark patch that stops the oxidation process. Once dry, this patch can be primed and painted.
Expert Tip
Place a tarp under your work area, especially when working on the driveway. Avoid oily stains on asphalt.
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Spray thickness
The viscosity of rust prevention spray can be thin or thick, and you should be aware of the differences between the extremes. Thinner rust prevention spray tends to be oil-based and is generally meant for use in areas that are protected from the elements. Thicker rust prevention spray tends to be more heavy-duty. While it’s true that a thicker spray can offer more protection over a longer period of time, it will not be able to reach the nooks and crannies that a thinner spray can.
Drying time
Drying time for rust prevention spray ranges from a few hours to a few days. That said, the average drying time is two to four hours. Drying time can be an important factor if you’re planning to paint the treated area, as a longer drying time can turn a simple project into a multi-day affair. Carefully consider the time factor when choosing a rust prevention spray.
Post-drying
Rust prevention spray may look different once dry. For example, a thicker spray might dry in a colorless, yellowish, or even dark hue. If you’re using a rust converter, darker hues are common.
The downside of a darker finish is that it will probably require extra work and time (more coats of primer or paint) to achieve the end result you’re shooting for.
Longevity
You may be wondering how long after application a rust prevention spray will do its job. The fact is it varies from one product to the next. You might prefer a long-lasting spray, so you don’t have to apply it as often. The manufacturer should give an indication of how long it’s likely to last and how often you’ll need to reapply it.
Expert Tip
Be mindful of weather conditions. Humidity can greatly affect outcomes.
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Features
Ingredients
Some rust prevention sprays are nontoxic; others are bristling with use warnings. Nontoxic spray is a better option if you have kids or pets around, but often, you may not have a choice. Many rust removers contain acid that can be harmful to the skin. On the other end of the spectrum are sprays containing lanolin, which is much easier on the hands.
Read the instructions and warnings to learn the best way to use a spray. The product literature should provide you with information on proper safety measures and whether the spray is flammable.
Lubrication
While all rust prevention sprays are used to treat rust, some can also be used as lubricant. Those that lubricate can be used to loosen rusted or frozen parts, lubricate hinges and wheels, and clean surfaces plagued with grease, tar, and other sticky substances.
Sprayer nozzle
A key element of any rust prevention spray is the spray nozzle. The best nozzles evenly apply the spray without allowing liquid to collect and solidify in the nozzle. Some sprays come with a straw attachment that allows for finer application and the ability to access hard-to-reach spaces.
Quantity
You can buy a single can of spray or, in some cases, a bundle of cans from the manufacturer. Bought in bulk, you are likely to save money on the product. If you’ve got a large project in mind, this may be ideal.
"Use caution when tackling multi-surface projects. If you are planning to use rust prevention spray on, say, a panel with metal and fiberglass or vinyl, first check with the manufacturer to verify that the spray can be used in this way."
STAFF
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Rust prevention spray prices
Inexpensive
Rust prevention sprays that cost less than $10 are usually simple one-type rust solutions for use on any metal surface. These no-frills options often come in the form of rust converters that lock down rust and can then be painted over.
Mid-range
In the $10 to $20 range, the cans of spray tend to be larger, and you will find more choice in terms of spray type. You’re more likely to get a better finish with a mid-range spray.
Expensive
Some rust prevention spray costs more than $20. Often, the higher price is due to the fact that you’re getting a multi-pack.
Expert Tip
Read the can about recommended storage temps. Garages may be too cold in some climates.
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Tips
- Consider a multipurpose spray. A product that combines several different types of spray — an inhibitor, a remover, a primer — allows you to achieve several different types of results without having to buy additional bottles of spray.
- Protect yourself. Many rust protection sprays include harsh chemicals. Wear gloves and a mask, and only use the spray outdoors or in a well-ventilated area.
- Buy enough for your project. You don’t want to find yourself three-quarters of the way through a job only to discover you are out of spray.
- Don’t use spray in areas that reach high temperatures. For example, you should not use rust spray on an exhaust pipe. Manufacturers generally recommend that you only use rust prevention spray on parts that stay under 200°F.
- Familiarize yourself with other rust prevention methods. These include regularly washing and waxing your vehicle, storing it under some form of cover (such as in a garage), and inspecting it regularly to catch any rust problems before they get out of hand.
FAQ
Q. Should I stick with a name-brand rust prevention spray?
A. While it may be tempting to save a few dollars on an off-brand rust prevention spray, you will probably be better off avoiding this. Brands with good reputations tend to make sprays that are more consistent and effective. You’re also more likely to experience better customer service, should you need it.
Q. Can I paint over rust prevention spray?
A. It depends on the spray. Some rust prevention sprays, like primers, are designed to act as binding agents between metal and paint. Rust prevention spray designed for other purposes may be less effective with paint. Always read the product specs and directions before use.
Q. What’s the difference between rust prevention spray and rust prevention paint?
A. Rust prevention products generally come in spray form or as a liquid you can apply with a cloth or paintbrush. The project you’re tackling will dictate what you need. Spray can cover a large area fast, making it an ideal choice for a sizable project. You can use a spray to reach nooks and crannies so no spot is left unprotected.
If you apply the product with a paintbrush, you will have added control over the application process. The project will likely take you longer and require more time to dry. This type of application usually results in a thicker layer of rust protection, which may appeal to you.
