Rust Converters vs. Rust Removers

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Rust, otherwise known as iron oxide, is a real pain in the neck as it makes metal surfaces lose aesthetic value and affects their structural integrity. If you’re planning a car restoration project or doing regular maintenance on a vehicle that has rusty parts, you understand how troublesome it is.  Fortunately, there’s no shortage of products to help deal with rust.

The two go-to professional options in most cases are rust removers and rust converters. There’s a huge difference between these two which doesn’t make it any easier to choose the right one for your needs. Below we walk you through the ins and outs of each and where they are suited for use.

Rust removers

Rust removers are formulations made of concentrated acids (mostly oxalic acid) as the main active ingredients used to separate rust from a metal surface. They cure rusty surfaces thus preventing the rust from spreading to areas that are still unaffected.

How do they work, and how are they applied?

Rust remover products typically work by reacting with the iron oxide and making it detach from the surface. This reaction amends the molecular structure of the surface. The area where the rust remover is to be applied has to be prepared by sanding away the excess rust.

The remover is then applied using a brush, and once the process is done, the surface can then be primed and painted. Most rust remover products are hazardous and can eat through the metal after clearing the rust. This is why it is crucial to monitor the acid and ensure it only removes the rust.

Rust converters

A rust converter is a chemical solution that usually has a tannic acid or phosphoric acid component that reacts with the rust to form ferric tannate or ferric phosphate, respectively. These bluish-black compounds formed as a result of the chemical reaction are inert and therefore act as barriers preventing further corrosion.

Most rust converters also have an organic polymer that works as a protective primer layer. This kind of rust converter product saves you time as you only need to apply one coat.

How do they work, and how are they applied?

There is no need to blast the surface to prepare it when using a rust converter. Only minimal preparation is required making the process less time-consuming. If flaking rust is present on the surface, it can be removed using a wire brush before applying the solution.

Removing this rust component and cleaning the resultant surface helps get rid of contaminants that can affect the conversion of iron oxide to iron tannate or phosphate. Note that you may need to apply several coats to get the job done, depending on how rusty the surface is.

Best rust remover and rust converter uses

It is important to clear rust as soon as you notice it has formed on your vehicle’s body or around some parts. Delaying the rust removal can end up costing you more when the rust damage becomes extensive.

Here are a few pointers to help you decide which option is suitable for your needs.

The best cases to use a rust remover are:

  • When the result you want to achieve is exposed rust-free metal.
  • If the area you want to clear is a mix of rust and paint or a mix of rust and bare metal.

A rust converter is, on the other hand, best applied:

  • On a surface with 100 % rust or on a surface with heavy rust.
  • If the surface you’re cleaning will be coated with paint afterward. This is because the resultant iron phosphate or tannate compounds are paintable.

Many car owners have a misconception that rust converters prevent rust formation completely. That is not the case as these solutions are not designed to be rustproof. Rather they form a layer that offers protection and prevents more corrosion while clearing away the already formed rust.

Wrap Up

Rust removers and converters are both excellent solutions, albeit suited to different purposes. The former will separate the rust from the metal surface being restored, while the latter will convert the rust into a stable paintable compound.

When deciding which one to use, consider the rust quantity on the surface you want to restore, the type of rusted object or surface, how you want to restore the surface, and the reason for restoring it. If you’re not sure which one to use, get professional advice from a qualified mechanic.