How to Remove Rust from Metal

Rust! To me, it’s the ultimate eye-sore. Besides being ugly, rust weakens metal. So to make your metal railings, outdoor furniture, garden tools, and hand tools last longer, you need to do something about it — now!

The bad news about rust is that you can’t ever stop it completely. Where metal, air, and moisture can be found, rust is sure to follow. The good news is, you can at least temporarily remove it and slow its return.

How you choose to remove rust often comes down to how much there is and the size and shape of the surface it’s on.

Most of the products we show are available at paint stores, hardware stores, and home centers. A few of the products are a bit more specialized, but they’re available on the internet.

Using Power Tools

The number-one rule of rust-busting is this: Always get rid of as much rust as you can, down to bare metal, if possible.

If you don’t, you’ve created the perfect starting point for more rust and eventually, you’ll be redoing the same area. You have better ways to use your time than to redo a project!

Removing Rust With A Cordless Drill

With decorative steel railings, where there are always bends and twists, a wire brush chucked into a cordless drill is the easiest way to remove rust (Photo 1).

Strip away rust quickly with a wire brush chucked in your electric drill. The brushes come in different wire grades (fine, medium and heavy) to match the degree of rust you’re removing. We’re using a medium-grade brush on our railing.

Wire brushes come in fine, medium and heavy grades. Either a fine or medium brush will work on light rust; save the heavy one for bad cases.

Removing Rust With A Sander

For de-rusting large, flat surfaces, try a power sander. A belt sander or palm sander will work, but you’ll get the best results with a random orbital sander (Photo 2).

Remove rust from larger areas with a power sander. A random orbital sander is a good choice. It works quickly and smoothly with great results. Start with a 40- to 60-grit sanding disk, depending on the degree of rust — the heavier the rust, the lower the grit number. Progress to higher numbered sanding disks (less grit) as the rust is removed, for a smooth finish.

The random sanding pattern works a large area (like the back of our metal lawn chair) and helps prevent sanding lines or gouges.

Removing Rust With Hand Tools

Sometimes the old ways are the best. Scraping and sanding with a little (or a lot of) muscle power may be old-fashioned, but it works!

Photo 3 shows a variety of rust-removing products.

Match the sanding or scraping tool to the project: A wire brush works on most surfaces; sanding cords and tapes are great for narrow gaps; steel wool and synthetic scraping pads work on all degrees of rust; sanding blocks are a good choice for flat surfaces; sanding sponges are great for sanding curves and other shapes; an English muffin is a lousy sanding tool, but a great snack!

Most of them are familiar. A couple may be new to you:

  • A wire brush loosens rust and cleans almost any metal surface.
  • Steel wool and the new synthetic scraping pads (fake steel wool) work on almost all degrees of rust.
  • Sanding blocks are great for flat surfaces. Some blocks use precut, adhesive-backed sand-paper. Others use regular sandpaper that you cut to fit and then wrap around the block.
  • A sanding sponge is flexible, so it's perfect for sanding curves and other-wise hard-to-sand shapes.
  • Sanding cords let you get into small gaps, like the kind you'll find on wrought iron railings (Photo 4). Cords come either flat or round and in different grits.

Clean out small gaps and spaces with a sanding cord. They’re available in different grits, much like conventional sand-paper. Work the cord back and forth—think of it as dental floss for metal.

How to Dissolve (or 'Convert') Rust

Trying to sand rust off some metal surfaces may be impossible — certainly a royal pain. When this happens, slip on a pair of rubber gloves and eye protection and spread on the naval jelly (Photo 5).

Apply naval jelly to dissolve heavy rust. Spread on a thick coating with a brush and let it work for 15 to 30 minutes. Then, rinse with water. Always wear gloves and eye protection — naval jelly contains phosphoric acid, which is caustic.

This old, reliable product dissolves rust well and is easy to use. Its gel formula keeps it in place, even on vertical surfaces. Just let it sit for 15 to 30 minutes, depending on how bad the rust is, then rinse it off with water.

An alternative to dissolving rust is to leave it in place and “convert” it. Rust converters are applied directly over the rust, and a chemical reaction seals the rust so new rust can’t develop. Then, just prime and paint — pretty slick! Read the label for specific drying times before applying primer or paint.

How to Remove Rust from Hand Tools

Have you ever noticed small rust spots on the tools in your toolbox? Want to stop the dots? Line your toolbox trays with rust preventive paper (Photo 6).

Line your toolbox trays with rust preventive paper. This specially impregnated paper keeps moisture—and rust spots—away.

This paper is impregnated with an antioxidant that gives off vapors that keep moisture away. And no moisture means no rust No muss or fuss, and it costs super cheap.

If there’s some rust on your hand tools, you can easily rub it off with steel wool. Start with a “0” or “00” grade steel wool and work up to a “000” or “0000” grade as the amount of rust decreases.

If you own a rotary grinding tool, such as a Dremel, you have one of the best power tools available for getting rid of rust. The small grinding, wire brush, and sanding heads let you work in tight places with great precision.

If you own a bench grinder, use a wire wheel to brush away rust from tools and other objects. Wire wheels come in fine to coarse grades. Always wear eye protection.

Anticorrosion Primers and Paints

You must apply primer to bare metal within 24 hours or rust will again begin to form. If it does, you’ll need to start all over again.

If there’s some rust left on what you’re painting and you didn’t use a converter, use a “direct-to-rust” primer/coating (Photo 7).

Apply “direct-to-rust” primer if there’s still some rust on the metal. These primers bond to the rust and encapsulate it, preventing it from spreading, and they prime the metal — all in one step.

These products bond to existing rust and prevent it from spreading, much like a converter.

Work in a well-ventilated area and wear a respirator as well.

Whether to spray or brush on the primer and paint depends on what you’re painting. Spray paint works best on intricate designs, such as stair railings. Brush-applied primer and paint work well for large, flat areas, such as metal storage sheds.

Be sure the primer and paint can be used on metal. Any brand-name paint will work (Photo 8), so it’s your choice, but try to stay with the same brand of primer and paint because they’re formulated to work together.

Primer and paint come in both spray and brush-applied formulas. Choose the application method that’s best for your project. Also, use a primer and paint from the same manufacturer since they’re formulated to work together.