Rust formation is a common problem with metal furniture like filing cabinets. Though unsightly, rusting is a natural process that can be effectively treated and prevented. With some effort and the right techniques, you can fully restore the look and integrity of your metal cabinets.

Why Rust Forms on Metal Surfaces

Rust is the result of a chemical reaction called oxidation that occurs when bare metal is exposed to moisture. The oxygen in water interacts with iron in the metal, forming rust – a flaky, reddish-brown compound. Filing cabinets are prone to rusting for a few reasons:

• Metal composition – Most are made of low-carbon steel which easily corrodes. Stainless steel has more rust resistance.
• Exposed edges – Rust often starts along unfinished edges, holes, scratches or joints.
• Moisture – Exposure to humidity or liquids like spills can initiate rusting.

If left untreated, rust can spread, weakening and damaging the metal. So addressing rust formation quickly is key to preserve your cabinets.

Cleaning Solutions for Rust Removal

There are several effective options for DIY rust removal from metal surfaces:

Vinegar

White vinegar is a mild acid that dissolves rust.

• Mix equal parts vinegar and water and apply it to rusted areas with a sponge or brush.
• Let it sit for at least one hour before scrubbing and rinsing off.
• For tougher rust, use undiluted vinegar and let it work overnight before scrubbing.

Baking Soda

Baking soda is a gentle abrasive that can lift rust when used in a paste.

• Make a paste with 3 parts baking soda to 1 part water.
• Apply to rusted spots and let sit for several hours before scrubbing.
• For better results, cover the paste with a plastic wrap to prevent drying out.

Commercial Rust Removers

Several commercial products are designed to break down and remove rust:

• Phosphoric acid – Sold as naval jelly, this clings to surfaces to dissolve rust.
• Tannic acid – Derived from plants, this mild acid converts rust into a water-soluble compound.
• Oxalic acid – Found in rust removers like Bar Keepers Friend, oxalic acid lifts rust chemically.
• Citric acid – White vinegar contains this mild acid but pure citric acid works faster.

Follow all safety instructions when using store-bought removers. Apply to rust per directions, let sit, then scrub and rinse.

Sandpaper

For small spots of surface rust, rubbing with fine grit sandpaper can efficiently scour it away. Focus on affected areas only and avoid overly scouring good metal.

Steel Wool

Super fine 000 or 0000 grade steel wool can buff out rust when used with a remover solution. Apply the solution first, let sit, then rub gently with steel wool in the direction of the metal grain. Rinse thoroughly after.

How to Clean Rust Off Metal Filing Cabinets

With the right supplies and techniques, you can revitalize old rusted filing cabinets. Here are the complete steps:

1. Remove Contents

Clear out all files and drawer contents to allow full access to the cabinet interior and exterior. This also prevents documents from being damaged during cleaning.

2. Wipe Down

Use a microfiber cloth to give cabinets an initial wipe down, removing any dirt or dust buildup.

3. Apply Rust Remover

Select a rust removal solution like vinegar, naval jelly or oxalic acid. Liberally apply the solution to all rusted areas using a brush, sponge or spray bottle.

4. Let Solution Sit

Allow remover to soak on the rust spots for at least one hour. For heavier rust, let sit overnight.

5. Scrub

Use a stiff nylon brush or abrasive sponge to scrub stained areas, lifting away rust residue. Apply elbow grease to remove stubborn spots.

6. Rinse

Thoroughly rinse cabinets with clean water to eliminate all traces of remover and rust. Dry with a towel immediately to prevent new moisture exposure.

7. Spot Treat

For any remaining rust spots, repeat steps 3 to 6, letting the solution soak longer before scrubbing again.

8. Sand Away Stains

If any light stains remain, gently rub them away using 320 grit sandpaper. Avoid scouring good metal.

9. Clean and Polish

Once fully de-rusted, wash cabinets with a pH-neutral cleaner. Apply a metal polish like Flitz to restore luster and protect the surface. Buff to a shine.

10. Maintain

Keep cabinets dry and touch up occasionally with fresh polish. Address any new rust spots quickly to prevent major damage.

Tips for Preventing Rust on Metal Filing Cabinets

A little preventive care goes a long way in keeping your filing cabinets free of rust long-term:

• Keep cabinets in a climate-controlled area away from moisture sources.
• Clean up spills quickly and dry any wet spots ASAP.
• Use polish to maintain a protective coating on the metal.
• Avoid nicking or scratching the metal finish.
• Raise cabinets off direct floor contact to prevent moisture exposure.
• Consider replacing heavily rusted cabinets made of thin, low-carbon steel. Opt for thicker 22+ gauge steel or stainless.
• New cabinets can be coated with a clear enamel paint for added rust protection on edges.
• Control humidity with dehumidifiers and increase ventilation.

When to Call for Professional Help

While many DIY options are available for removing rust, extensive corrosion may require professional intervention:

• Rust has penetrated through the full metal thickness, causing pitting or holes.
• Supportive inner cabinet walls have become structurally compromised by pervasive rust.
• The filing cabinet doors or drawers are no longer functioning properly due to rust damage.
• Electrical components have become hazardous due to rust exposure.
• Special confined space training is needed to safely access and clean certain cabinet areas.
• Intense built-up rust exists that is resistant to home cleaning methods.

Restore the Function and Charm of Your Filing Cabinets

Don’t resign yourself to ugly corroded file cabinets that damage important documents. With the powerful rust removers and cleaning techniques available, you can fully eliminate rust and prevent its return. A small time investment in DIY rust removal and maintenance can restore the look, stability and functionality of your metal filing system.

Conclusion

Rust formation on metal filing cabinets is a common nuisance but one that can be effectively treated using the right solutions and techniques. Mild acids like vinegar or citric acid work to dissolve rust so it can be scrubbed away, while baking soda or sanding take a more abrasive approach. Commercial rust removers utilize acids tailored for metal restoration. With some elbow grease and patience, old rust stains can be eliminated and further corrosion prevented, bringing new life back into your filing system. Addressing rust issues promptly preserves the integrity of your cabinets for reliable long-term document storage.