7 Best Rust Converters That Might Just Save You a Panel Replacement

Rust is a problem that can plague vehicles of any age.

Environmental conditions, poor maintenance, and other factors can contribute to corrosion. Going to the mechanic or body shop for cosmetic issues isn’t an option for most of us, being too costly. Rust converters are a great – and less expensive – alternative to small rusty issues.

That being said, choosing the best rust converter for cars can be tricky. Every car is unique, rust problems can differ in importance and position, and many products are unique. So there are a few considerations to bear in mind when buying.

In this article, we’re going to explain how these products work and the benefits of using one. You’ll also learn what differentiates them from rust removers.

Next, you’ll get familiar with the different types and how to buy the correct one for your specific needs. Lastly, you can read through our top recommended brands on the market today.

Quick Links to Our Top Recommendations for Best Rust Converter

• Rust Converter ULTRA, Highly Effective Professional Grade Rust Repair
• VHT SP229 Rust Convertor Can – 10.25 oz.
• Corroseal Water-Based Rust Converter Metal Primer
• PlastiKote 624 Rust Converter
• Permatex Rust Treatment, 10.25 oz. net Aerosol Can (Pack of 12)
• MROChem Black Star Rust Converter – Converts Rust on Any Steel Surface
• GEMPLER’S Eco-Friendly Rust Converter and Primer All-in-One

Note: Clicking the above links will take you to further information, current prices and customer reviews on Amazon.

What is a Rust Converter? What Does it Do?

These chemical products can do a couple of things. As the name suggests, they convert rust into a different, acceptable, more manageable material and do so by a chemical reaction.

Next, it prevents rust patches from spreading.

Lastly, applying one can serve as a base for future treatment. For instance, you can eventually apply primer and paint to the affected area.

The exact abilities can vary based on the brand. It all depends on the formula.

How Does Rust Happen?

Before we dive into how these converters work, it’s important to understand what rust is. You should also know what makes your car susceptible to this unpleasant phenomenon.

Rust is a form of corrosion that affects iron and iron alloys, materials that most vehicle bodies are made from. It’s a result of chemical reactions that wear away the exposed material (metal) with time. The official name for the whole process is oxidation.

Oxidation is the result of environmental factors. Gases, liquids, acids, and salts wear down the exposed surface of the metal. It can take months or years to occur, depending on external conditions.

Interestingly, rust transforms the composition of the affected metal. The scientific name for the outcome of this metamorphosis is hydrated iron oxide. To simplify it, hydrated iron oxide is a mix of oxygen, iron, and water.

Everyday occurrences like rainwater, humidity, and heat can provoke rust. The more your vehicle is subjected to these elements, the higher the likelihood of oxidation.

For example, let’s say you live near the sea and park your ride outdoors. Your car is probably exposed to saltwater spray and high humidity. It’s more likely to oxidize and become rusty than a vehicle parked in a temperature-controlled garage.

Nowadays modern vehicles are well-protected against rust. The paint on newer models isn’t just for aesthetic purposes. It provides protection to vulnerable metal surfaces from the outside world.

The majority of today’s automotive paints are packed with additives. These compounds enhance the quality, lifespan, and appearance of automotive paint. For example, silicone additives boost weather resistance. Dispersants make sure the pigments in paint stay stable, so it doesn’t clump. You get the general idea—and there are many more besides these.

These finishes can include substances that are anti-abrasion, anti-corrosion, and heat-resistant. They can reduce the risk of scratches and heat bubbles, as well as oxidation. For this reason, newer vehicles have a lower risk of rust than classic antiques. Paint and finishes on older models of cars don’t have as many additives.

Unfortunately, even these modern-day treatments don’t make vehicles permanently immune. If the metal of your car is exposed to the outside air, rust is always a possibility. Even the most cautious vehicle owner can’t keep their investments pristine forever. Accidents can happen, scratching away your finish and paint, leaving bare metal exposed to the elements which can start to form rust.

Concealing the problem with paint without treating it first is a bad idea. To begin with, automotive paint won’t bond well to a corroding surface. Plus, paint won’t solve the underlying issue, it will only hide it from sight until it breaks through again.

So what you want, is a rust converter.

How do Rust Converters Work?

You now know that these chemicals can treat rust spots and slow or stop them from expanding. It’s time to take your knowledge to the next level and delve into the science behind these substances.

The typical product works by chemical transformation, by actual rust conversion into a new and different material. Most of them are made from two primary active ingredients. These are weak acids (or blends of chemicals) combined with organic polymers. The latter is typically 2-Butoxyethanol.

It may sound contradictory to use acid on your vehicle. In actual fact, these acids (e.g., tannic acid or phosphoric acid) won’t cause further harm.

Polymers are made of large molecules and can be natural or synthetic. Polymer-based materials can provide structure, resist high temperatures, and have other practical abilities. Numerous brands of car paint sealers, motor engine oil, and oil additives include polymers.

The first part of the conversion process begins with the acid or chemical blend. This ingredient works by bonding to the rust or hydrated iron oxide. The rust then reacts to the acid. If the active ingredient is tannic acid, it will be turned into ferric tannate.

If it’s a phosphoric acid blend, the reaction will result in a ferric phosphate. Regardless, it has now been converted into a controllable substance. This isn’t one of those invisible chemical reactions either. The rust will turn into a dark, blue-black color. You won’t see the characteristic orange-red of oxidation afterward.

Once the converter substance has done its job, the organic polymers come into play. They form a layer over the newly converted material. This layer functions as an airtight seal, preventing further oxidation from occurring in that area again. Bear in mind that moisture and oxygen are the culprits here. To be effective, the seal must be impenetrable by these elements.

As I said, you’ll be left with a dark blue-black patch on the area. If this sounds just as unattractive, don’t worry. Unlike rust, you should be able to paint over this without any trouble.

We mentioned earlier that the formulas are specific to the manufacturer. Certain rust converters can include other ingredients. For example, a converter can contain solvents or other chemicals to speed up the process. In turn, this will shorten the drying and curing time.

What are the Benefits of Using One?

There are numerous advantages to using a rust converter. If you’re still not certain

about using it on your vehicle, consider the following:

Improve Appearance

Let’s be honest here. When we see any machine covered in rust spots, we think of neglect. By safely converting hydrated iron oxide, you can then paint the offending area.

Even if you don’t repaint it, a black spot might still look better than a bright red rust patch. If you have a dark paint job, you might even be able to leave it as it is, depending on the color.

Prevent Serious Degradation

There is a short list of car troubles you can safely ignore. Surface corrosion is one that falls somewhere in the middle between mild and severe. If you decide not to act, you have to keep a careful eye on it.

When you leave this decay untended, it can eventually spread. On the upper portion of your vehicle’s body, oxidation is merely an unattractive sight. You can think of this like a zit or a pimple on your skin—unsightly, but certainly not fatal.

If the problem on your vehicle continues to escalate, however, the consequences can be dire. The affected area can start to develop holes. If left for long enough, affected parts (such as side panels) can fall apart.

Avoid Effort and Expense

The only surefire ways to eliminate rust from cars is by sandblasting the metal or using a rust remover product. If you only have a few small spots here and there, these are needlessly invasive processes.

Converting the corrosion instead of removing it can save you money and time. All you have to do is treat your vehicle and then repaint the spot (or spots.).

Difference Between a Rust Converter and a Rust Remover?

Rust removers and converters may sound similar, but they aren’t. Remember that converters don’t remove the corrosion—they alter it instead.

In a sense, this does get rid of the oxidation but doesn’t remove it. Contrastingly, rust removers eradicate rust entirely.

In order to do this, though, these removers are often harsher, made with strong rather than weak acids. These chemicals attack rust by dissolving it entirely. The goal is to reveal the bare metal underneath.

Rust removers tend to be unforgiving of human error. If you don’t follow instructions explicitly, you could end up destroying metal as well. These products have to be used carefully and thoroughly cleaned off, as residue can be destructive.

You’ll also have to take measures to cover up that exposed metal quickly. Otherwise, you’ll risk new rust forming in the same spot.

Types of Rust Converters

These handy chemicals come in various forms. You can choose between gel, liquid, or powder.

Gel: In this form, you have more control over application, since gel is viscous.

Liquid: These can be similar in consistency to water, or thicker like syrup. Liquid converters may come in bottles or sprays.

Powder: Products that are in powder form may need to be mixed with water before application. Some powders, however, can be applied directly as they are.

Buying Guide – What to Look for in the Best Rust Converter

Before you get to work on converting rust on your car, take a moment. Not all manufacturers produce the same quality and type of product.

You don’t want to purchase one of these chemicals, only to find it’s not suitable for your needs. Every vehicle is unique, and so is every vehicle owner.

Preparation

Check to find out if any vehicle preparation is required before application. Not everyone wants to take the time and trouble to purchase special products and scrub down their vehicle beforehand.

Application Method

The application method ties into the form of the product you choose. Applications of liquid, gel, and powder rust converters are all distinct from each other.

Check the guidelines to know what you should expect to do. Will you have to mix it with water? If this is the case, can you use it immediately afterward or will you have to wait for it to set? Does it have to be shaken or stirred repeatedly?

This may be a lot of messing around if you’re only treating one small spot.

If you have a large amount of oxidation to treat, you might want something that can be applied rapidly and easily.

Take a look at the container too. If you choose a liquid variation and it requires dilution, you want it to be easy to pour and measure out. In cold weather conditions, it can be a fight to get a thicker gel to pour. A powder can be challenging to apply if the spots are on a vertical panel.

Do you need tools to apply the product with or are they supplied? You may have to provide a brush or other applicator, for example.

Time to Dry and Cure

This could be a chief consideration influencing your selection. Certain brands require that you leave the substance to dry for several hours.

If you have a garage, drying and curing time might not be as much of a concern. Those of you who don’t have sheltered parking, however, should read the instructions carefully.

A sudden squall of rain can wash away your chosen product before it has time to take effect, or even wash the solution over non-oxidized paintwork, causing damage. If it’s too cold or hot outdoors, some products may be ineffective.

Cleanup, Safety, And Toxicity

Safety should always be a concern when you’re dealing with chemicals. If you’re doing it yourself, treating the corrosion will be a hands-on process.

You’ll have to apply it to the treatment area. Then, the product may have to be cleaned off. Certain types are simple to remove, requiring only plain soap and water.

With other converters, however, you might have to buy specialized detergents for a more thorough cleaning. If this doesn’t appeal to you, pick a brand that specifies easy cleanup, if any.

Once again, think about the types available. If you’re wary about handling the product, you might favor gel or a rust converter spray. Powders can be accidentally inhaled, liquids can drip or spill, etc.

On the same note, certain formulas are designed with safety in mind. They are less toxic and can be applied indoors. Others are stronger and must be used outdoors or in well-ventilated areas.

Certain chemicals in rust converters can cause respiratory issues if inhaled. They can also result in chemical burns if left on your skin. Always take extra precautions when applying these sorts of treatments to your vehicle.

Coverage

The majority of rust converters on the market state a specific coverage per gallon. The coverage affects the price and ease of use. If you see a brand with a high price tag, ensure that the coverage is worth it.

Best Rust Converters for Cars – a Detailed Look at Our Top Recommendations

Below, we’ve listed our choice of the top products on the market to tackle corrosion on your automobile. We’re sure You’re bound to find one that meets your needs.

Rust Converter Ultra, Professional Grade Rust Repair

If you have more than one car or a lot of areas to treat, this multipurpose liquid product might work for you. To tackle the corrosion, all you’ll need is one to two thin coats of this solution.

This means that the one-gallon container will last a long time. As long as you’re not treating porous metals, coverage is rated at 500 square feet. That’s more than enough for the occasional oxidizing scratch or dent on your vehicle.

A great feature of this brand is convenience. You won’t have to do anything but shake the bottle, and it’s ready to use. You just have to thoroughly clean the rusted metal to be treated and then apply the liquid with a paintbrush, spray, or roller.

There’s no need to trash your application equipment when you’re done. Washing your brush or roller with plain soap and water will do the trick. And it dries rapidly—all you’ll need is 20 minutes.

Wait 48 hours for the area to cure before painting over the treated parts. Primer isn’t necessary, you can use any automotive paint directly on the converted corrosion.

You can also use Ultra on more than just your automobiles. It’s compatible with any metal surface. Rejuvenate iron railings, old shovels, worn out machinery, or whatever else you want.

Specification and Feature List

• Bottle capacity: 1 gallon.
• Coverage: 500 square feet per gallon on smooth surfaces.
• Allow 20 minutes to dry and 48 hours to cure.
• No thinning required, ready-to-use liquid.
• Can be used on other equipment, not just cars.
• Must be applied in a well-ventilated area.

What We Like

• Generous coverage per bottle.
• Short drying time.
• Can be used straight out of the bottle.
• Cleans off application equipment with soap and water.
• No need for primer before painting.
• Treats more than just your automobiles.

What We Don’t Like

• Can wash off with time if not painted.
• May leave a sheen on surrounding metal.
• Lengthy cure time.

Summary

If extensive coverage is what you need, Ultra’s liquid formula will appeal to you. It won’t damage your application equipment and can be painted over without primer, although you do need to wait 48 hours.

If you’re interested in this product, check it out here:

Check Price at Amazon

Vht Sp229 Rust Converter Can

This VHT product is ideal for users who are uncomfortable with chemicals. The spray can enables you to use this liquid without rollers, brushes, or other equipment.

If you like to get hands-on with your automobile, this spray is for you. The same is true for vehicle owners who want to have more control in the process.

You’ll need to clear away as much of the decaying particles off as you can. If your car is more than just a daily driver (e.g. an antique or classic car) you’ll want to be involved. Brushing on a product and forgetting about it isn’t as satisfying.

The most challenging part is going to be the preparation. After you’ve completed your sanding and scrubbing, though, just spray VHT on. It can be applied to metal, body filler, and fiberglass surfaces.

You’ll see evidence that the formula is working almost immediately. As soon as the spray comes in contact, the corroded metal will turn black. Apply 2-3 coats. The liquid dries rapidly, and you should leave no more than two minutes between coats.

The seal formed by this product is durable and can be sanded smooth. You can paint over it after the 24 hour cure time.

Specification and Feature List

• Can capacity: 10.25 ounces.
• Available as a pack of six or a single can.
• Liquid, administered by spray.
• Treatment: apply two to three light coats.
• Allow 24 hours to cure.
• Formulated for application over metal, fiberglass, or body filler.
• Must be used in a well-ventilated area.
• Full instructions printed on each can.

What We Like

• Spray-can makes for less mess.
• Great for owners who take pride in working on their cars.
• Highly effective on early-stage oxidation.
• Can be sprayed over body filler and fiberglass.
• Sands down to a smooth base for automotive paint.
• Immediate, visible reaction.

What We Don’t Like

• Potent chemicals—preferable to wear protective gear.
• A lot of effort involved in preparation.
• May not work on moderate to advanced corrosion.

Summary

If you love to get up close and personal with your automobile, this spray from VHT is for you. It will handle the only thing you can’t do—chemically converting oxidation.

If you’d like to buy a can (or six) for yourself, click this link:

Check Price at Amazon

Corroseal Water-Based Rust Converter Metal Primer

Corroseal is a latex primer and chemical converter in one bottle. One of the major advantages of this brand is it’s user-friendly.

You get a choice of three different bottle sizes to fit your needs: 1 quart, 1 gallon, or 5 gallons. This will avoid waste, or running out before you’re finished.

You’ll want to try Corroseal if you dread the thought of effort-intensive preparation. This liquid treatment can be brushed, sprayed, or rolled on almost instantly. All you’ll be responsible for is surface prep, cleaning off loose rust and debris. You won’t have to sandblast, scrub, or scrape anything off before use.

Comprehensive guidelines ensure you won’t be left confused at any point. These feature practical images for extra reassurance. You can compare what you see on your car to the photos. This way, you’ll know if Corroseal is working as it should. If not, you’ll know what the problem is (e.g., improper cleaning).

Another advantage of Corroseal is it’s safer than some other chemicals. The liquid is non-corrosive, so it can’t wear away at metal. It’s also non-flammable.

Specification and Feature List

• Bottle capacity: 1 quart, 1 gallon, or 5 gallons.
• Coverage: 200 to 250 square feet per gallon.
• Liquid formula.
• Treatment: apply directly to corroded metal.
• Cure time: 24 hours.
• Includes latex metal primer.
• Cleans off with soap and water.
• Non-flammable and non-corrosive.

What We Like

• Safer than other alternatives.
• Choice of bottle sizes.
• Clear instructions.
• Primer included.
• Straightforward to apply.
• Hardly any automobile preparation needed.

What We Don’t Like

• Must be painted soon after treatment.
• Hard to measure out product in larger containers.
• Ineffective on advanced metal degradation.

Summary

This inclusive product serves as a two-in-one deal—latex primer and corrosion converter. A detailed manual will make addressing metal oxidation on your car a breeze.

Learn more about the Corroseal water-based solution here:

Check Price at Amazon

Plastikote 624 Rust Converter, 16 Oz .

If toxicity is a concern for you, this PlastiKote liquid is an attractive choice. The water-based formula is environmentally friendly, non-toxic and non-flammable. However, there is a warning on the bottle regarding harmful vapor, so make sure you use the product in a well-ventilated area.

You can either use a brush or roller to apply this liquid. However, be careful if any gets on your skin or clothing, as it will stain. Don’t be skeptical of the watery consistency: thin coats are recommended. You’ll be able to treat multiple or larger corroded spots without running out.

Vehicle owners who cherish a flawless paint job can take advantage of PlastiKote.

This liquid won’t foam or bubble and will create a shellac-like seal when dried. After curing it can either be primed and painted directly or sanded down for your primer and paint to go on smoothly. Bleed-through is also unlikely.

Specification and Feature List

• Bottle capacity: 16 ounces.
• Liquid.
• Non-toxic and non-flammable.
• Treatment: apply two coats.

What We Like

• A little goes a long way.
• Forms a hard, smooth seal.
• Environmentally-friendly.
• Non-toxic.
• Won’t bubble, bleed through, or foam.

What We Don’t Like

• Will drip if applied too thick.
• Hard to clean off foam rollers and brushes after use.

Summary

This non-toxic substance is free from harsh, potentially dangerous chemicals and is environmentally friendly. You’ll end up with a bubble-free surface that’ll look brand new once painted.

If you’re curious to see this PlastiKote product for yourself, follow the link below:

Check Price at Amazon

Permatex Rust Treatment, Aerosol Can

This fast-drying liquid is successful at treating surface corrosion. If you want to stop the progression of mild metal degradation, Permatex is ideal.

There’s not much you have to do beforehand. Preparing your car is as low-effort as using the aerosol spray itself. Cleaning the rusted surface to be treated and drying it off beforehand is all that’s required.

The spray has a consistency that is neither too thin or thick. It won’t drip off your car, but at the same time won’t settle in a clump.

It dries quickly, and the reaction is immediate. You’ll witness the trademark orange-red streaks or spots turn dark within minutes. Permatex bonds tightly to the metal. Even if it isn’t painted over, it won’t chip, flake, or scratch off easily.

This solid seal is an excellent base for primer and automotive paint. It isn’t prone to bubbling, making for a seamless paint job.

Another advantage is that this spray is temperature-resistant. It has a functional range of 50 to 90 degrees Fahrenheit. As long as the metal you’re treating isn’t over 200 degrees Fahrenheit, you can get spraying. If you live in a hot region with no garage, this is practical.

Specification and Feature List

• Can capacity: 10.25 ounces.
• Available as a pack of 12 or a single can.
• Also available in liquid form.
• Treatment: apply two to three thin coats within five minutes of each other.
• Liquid, administered by spray.
• Allow 24 hours cure time before reapplying topcoat.
• Suitable for body-filler and fiberglass.
• Must be used in a well-ventilated area.

What We Like

• Easy to use.
• Forms a tough bond.
• Conversion takes place within minutes.
• Good consistency.
• Doesn’t have to be painted over immediately.
• Undemanding vehicle preparation.
• Effective on surface rust.
• Temperature-resistant.

What We Don’t Like

• Not recommended for use on exterior sheet metal repairs.
• Strong chemical odor.

Summary

This rust converter is tough-bonding and successful at combating early-stage oxidation on your vehicle. It’s great for car owners living in hot climates too.

If you’re thinking about purchasing a can, click this link:

Check Price at Amazon

Mrochem Black Star Rust Converter

This rust converter is excellent for people who like to buy in bulk. This liquid can be purchased in containers ranging from 1 to 5 gallons. You’ll have an abundance of product for your vehicle and other rusting metal surfaces.

A thin coating on a paintbrush or roller is sufficient. This isn’t the type of liquid you have to drench your car in. Or, if you want to keep a distance from the chemical, you can use it in a spray bottle.

MROChem Black Star is white in color. You’ll be able to see it as you cover your corroded metal surfaces. Unlike clear liquids, you won’t have to go overboard to be sure you’re covering the area. Any excess liquid can be wiped off with water and soap. If you forget, the product will come off your vehicle naturally. Rainfall and exposure to the elements will take care of that for you.

MROChem forms a protective coating. The targeted area is unlikely to corrode again, whether you paint over it or not. If you do want to paint, the MROChem formula is a stable primer. It’ll appear as though the treated section has been covered in matte spray paint. You can put automotive paint over this without an additional primer.

Specification and Feature List

• Bottle capacity: Four sizes, between 1 and 5 gallons.
• Coverage: 400 to 500 square feet per gallon.
• Liquid.
• Dries within 20 minutes.
• Acts as a primer.

What We Like

• Converted surface is matte, can serve as paint primer.
• Consistency is easy to brush or roll on.
• Wiping excess product off isn’t hard.
• No need to scrub or sandblast your car.
• Lots of coverage with minimal quantity.
• Protects treated area from corroding again.

What We Don’t Like

• Can leave stubborn stains on other surfaces (e.g. concrete).
• May need more than one application.

Summary

This long-lasting liquid has generous coverage and is an excellent primer surface for paint. You can rest assured oxidation won’t rear its ugly head again on treated metal.

If you’re eager to buy MROChem Black Star, take a look at it here:

Check Price at Amazon

GEMPLER’S Eco-Friendly Rust Converter and Primer All-In-One

Gempler’s liquid formula is a potent weapon against oxidation on your vehicle. At the same time, it’s environmentally friendly and less toxic than other brands.

Preparation and treatment of your car with Gempler’s is practically effortless. Cleaning affected surfaces should be done thoroughly, but not intensively. Corrosion won’t have to be scrubbed or blasted off. Use a paintbrush or sponge to apply the liquid to the area.

You can expect noticeable improvement even with extensive corrosion. You may have to use more than the recommended two coats, but it should work.

The standout feature of Gempler’s product is it doesn’t only convert rust. It also inhibits future corrosion. Once applied, the treated part of your car shouldn’t oxidize again. This is great for those of you with more vulnerable automobiles. For example, if you live close to the sea or in a humid climate.

You can paint over the converted oxidation after 48 hours. The ingredients also consist of a primer. A gentle formula doesn’t necessarily mean a weak one. The anti-rusting effects of this liquid should last you long-term.

The 1-gallon bottle will cover up to 500 square feet. If you’re going to be applying this liquid exclusively to vehicles, it could last you for years.

Specification and Feature List

• Bottle capacity: 1 gallon.
• Coverage: up to 500 square feet per gallon on smooth surfaces.
• Liquid.
• Treatment: apply two coats.
• Non-flammable and environmentally friendly.

What We Like

• Cleans off with water.
• Less toxic than other alternatives.
• Works on moderate to severe corrosion.
• Protects treated areas from rust formation.
• Long-lasting.
• Serves as a primer.

What We Don’t Like

• Product must be kept above freezing point.

Summary

This rust converter is ideal for long-term corrosion prevention. If your car is vulnerable, you’ll want to buy a gallon of Gempler’s to have on hand.

Click the link below to discover more about this product:

Check Price at Amazon

Final Thoughts

Now that you’re armed with all this information, we hope you’ve found a product that suits you and your need. The best rust converter for cars isn’t going to be the same brand for everyone and thought must go into which you buy. Following our advice above should see you right though.

Seeing corroding metal on your vehicle can be a shock. Using one of these products should be a priority, before you get to the point of having to take more extreme measures.

If you have any feedback or questions for us, please do tell us in the comments below. We’re always happy to hear from you. We’ll get back to each and every one of you!