Rust formation is a common problem with metal cabinets, especially if they are placed in damp areas like basements or bathrooms. While rust compromises both the appearance and structural integrity of metal cabinets, the good news is that it can be removed with some effort and the right techniques. This comprehensive guide will walk you through various effective methods for removing rust from metal cabinets and restoring them to their original glory.
Cleaning and Preparing the Metal Surface
Before applying any rust removal solutions, it is important to thoroughly clean the metal surface to get rid of loose rust flakes, dirt, oil and other contaminants. This allows for maximum contact between the metal and the rust remover. Here are the steps for preparation:
Remove Loose Rust with a Wire Brush
Use a stiff wire brush to scrub off all the loose, flaky rust on the cabinets. This helps remove the outermost rust layer and allows better penetration of the rust remover into the metal. Focus on scrubbing rust from edges, bolts, hinges and other hard-to-reach areas.
Be sure to sweep away the rust debris after scrubbing to prevent recontamination of the surface. Wear gloves and eye protection during wire brushing.
Clean with Soap and Water
Mix a mild detergent like dish soap with warm water in a bucket. Use a sponge or soft cloth to wipe down the entire metal cabinet surface – front, back, top, sides and interior.
This helps get rid of grease, dirt and other contaminants like skin oils that can interfere with rust removal. Rinse thoroughly after cleaning and let the metal air dry.
Remove Stuck-On Grime with a Degreaser
For oily grimy deposits that dont come off with plain soap and water, use a citrus or alkaline degreaser. Apply the degreaser onto the metal and let it sit for 5 minutes before scrubbing with a stiff nylon brush.
Powerful degreasers help dissolve and displace stuck-on oily films for more effective rust removal. Rinse off thoroughly after scrubbing.
Sand Down Stubborn Rust Spots
Use 100-120 grit sandpaper to manually sand away any remaining swollen rust spots. Focus on sanding bumpy rust mounds and rust pitting.
Sanding smoothens the metal surface for better adhesion of rust converters and metal primers later. Wipe clean after sanding.
Rust Removal Methods
Once the metal surface is cleaned and prepped, you can now use special solutions to get rid of rust. Here are some of the most effective DIY rust removal techniques for metal cabinets:
Citric Acid Bath
Make a citric acid cleaning solution by mixing 1 part citric acid powder with 2 parts warm water. You can find citric acid in pharmacies or online.
Submerge rusty cabinet parts in the citric acid bath or apply it directly on vertical surfaces with a brush. Let it sit for 1-2 hours. Citric acid reacts with the rust and converts it into a water-soluble compound that can be rinsed off.
For heavy rust, you may need to agitate with a brush while immersed and make a stronger 1:1 citric acid solution. Rinse thoroughly and dry the metal well after treatment. Wear rubber gloves when handling citric acid.
Oxalic Acid Rust Remover
Oxalic acid is another mild acid that effectively removes light to moderate rust on metal with minimal damage to the base surface. Make a 10% oxalic acid solution by dissolving 100g of oxalic acid crystals in 1 liter warm water.
Apply it on the rusted cabinet with a nylon brush and let it sit for 15-20 minutes before rinsing. Repeat if needed for thick rust. Rinse and dry thoroughly after use. Oxalic acid removes rust through a similar chemical reaction as citric acid.
Vinegar Soak
Plain white vinegar is a multipurpose acidic cleaner that can remove light surface rust on metals. Make a 50% vinegar solution by mixing equal parts white vinegar and water.
Soak a cloth in the solution and use it to wipe down the rusty cabinet surface. Let the vinegar sit on the metal for 10-15 minutes before rinsing with water. The acetic acid in vinegar reacts with the rust to form soluble iron acetates.
For heavier rust, you may need to agitate with a brush or use full-strength vinegar. It may take several treatments to completely remove rust using vinegar.
Baking Soda and Vinegar
Mix 2-3 tablespoons baking soda with 1 cup white vinegar to make a foamy rust removal solution. Apply it on the metal surface with a damp sponge or brush. Let it fizz on the rust for 5 minutes.
The combined effect of acetic acid and abrasive baking soda helps lift off stubborn rust deposits. For vertical surfaces, make a thick paste with more baking soda and apply with a plastic scouring pad. Rinse thoroughly after treatment.
Naval Jelly Rust Dissolver Gel
Naval jelly is a commercially available phosphoric acid-based gel formulated to cling to metal surfaces and dissolve rust. Apply a thick coat of naval jelly gel on the rusted areas and allow to work for 30 mins to 1 hour.
Scrub with a plastic scouring pad to remove loosened rust. Rinse thoroughly. Repeat for dense rust buildup. Naval jelly converts iron oxide into iron phosphate for easy removal.
It is safer than muriatic acid and does not need dilution. Wear gloves when handling naval jelly.
Muriatic Acid Rust Remover
Also called hydrochloric acid, muriatic acid is an aggressive rust removal option for heavily rusted metal. Dilute muriatic acid 1:10 with water and apply onto the rusted surface with an acid-resistant brush.
Let it work for 10-15 minutes before scrubbing and rinsing. Use extreme caution when handling muriatic acid as it can cause severe burns. Wear acid-proof gloves, goggles and clothing. Work in a well-ventilated area.
Rust Converter Liquid
Rust converters contain tannic or phosphoric acid that reacts with rust to convert it into an inert black protective coating. Brush on a coat of rust converter liquid over rusted areas, leaving it undisturbed for 2-3 hours.
The rust turns into a black film which can then be painted over. Rust converters are easy to apply compared to other acids and stop further rust formation. Allow sufficient drying time before painting.
Electrolysis Rust Removal
Electrolysis involves running a low electrical current through a rusty object submerged in an electrolyte solution to dissolve rust. This method is best suited for small metal parts and needs special equipment – a battery charger, electrodes, basin and washing soda electrolyte.
The electrical current causes the iron oxide rust to transform into a water-soluble compound. Rinse off the dissolved rust residues after electrolysis treatment. This leaves behind a clean, rust-free metal surface.
Sandblasting
Sandblasting, or abrasive blasting, rapidly strips off rust by propelling a high-pressure stream of abrasive media onto the metal surface. It is the quickest way to remove heavy rust buildup.
Media like baking soda, dry ice, glass beads, walnut shells, etc. can be used based on the metal substrate. Professional sandblasting gives the best results but smaller handheld abrasive blasters are also available.
The metal surface needs to be primed and painted immediately after sandblasting to prevent flash rust formation. Sandblasting also leaves behind a coarse pebbly texture.
Grinding
For removing stubborn rust spots in limited areas, use an angle grinder or rotary tool with a sanding disc or wire wheel brush. Pick coarse grit abrasive discs for heavy rust removal. Grinding removes not just rust but also a thin layer of underlying metal.
So use it sparingly only on localised rust spots. Wear a dust mask and eye protection when grinding metal. The metal will need priming and repainting after grinding.
Preventing Rust Reformation
Once you have removed all the rust, it is equally important to take preventive steps to stop recurrence of rust on metal cabinets:
Dry Completely
Ensure no moisture or dampness remains on the metal surface after rust removal. Use lint-free cloths to wipe cabinet frames, doors, handles and other hardware. Let the cabinets air dry thoroughly before repainting or applying any protective coatings.
Remove Rust from Crevices
Check inside cabinet joints, hinges, nail holes, metal brackets etc. for trapped moisture or remaining rust. Use cotton swabs dipped in rust removers to extract rust from these crevices. Ensure these areas are bone dry before sealing.
Apply Rust Preventive Spray
Use a rust inhibitive spray that leaves an invisible protective coating on the metal surface after rust removal. These contain waxes or oils that displace moisture and prevent rusting. Apply evenly on cabinet frames, doors, tracks and hardware.
Prime and Repaint
Applying a rust-inhibiting metal primer immediately after cleaning creates a protective barrier preventing moisture from reaching the metal. Use an oil-based or epoxy primer formulated for metal before repainting cabinets.
Follow with a couple coats of durable cabinet enamel paint. Make sure to paint backs, undersides and insides.
Improve Ventilation
Open up enclosed cabinet bases to allow air flow and circulation inside. Install ventilation slots or drill holes near the top back of metal cabinets. Improve overall ventilation in damp areas like basements.
Keep cabinets away from direct contact with water sources.
Apply Silicone Sealant
Seal all joints, gaps, and seams on the cabinets using a clear waterproof silicone sealant. This prevents moisture entry. Apply along the wall-cabinet junction, where the counter top meets the cabinet, door frames and edges etc.
Regular Maintenance
Check metal cabinets periodically for early signs of rust spots. Immediately clean and apply rust converter on affected areas to arrest rust spread. Keep cabinet surfaces free of moisture, grease and grime.
FAQs About Removing Rust from Metal Cabinets
How do you get rust off cabinets without removing the paint?
For localized rust spots on painted metal cabinets, use rust removal pastes or mild acids like oxalic acid that will not damage existing paint.
Apply only on rusted areas with a brush and wipe off. Vinegar or naval jelly gel also works well. Do not use sandpaper or anything too abrasive when paint needs to stay on.
What damage does rust do to cabinets?
As rust formation progresses, it leads to swelling, flaking, pitting and discoloration of the metal surface. Rust expands to several times the volume of original metal, causing paint to crack and peel.
It makes the metal porous and structurally weaker over time. Rust staining also looks unsightly on visible cabinet surfaces. Severe long-term rust damage necessitates replacement of entire cabinets.
What kind of vinegar removes rust?
White distilled vinegar, apple cider vinegar or red wine vinegar – all work to remove rust due to their acidic nature. White vinegar is the most commonly used and effective since it contains about 5% acetic acid. Do not use balsamic vinegar.
Always use full-strength undiluted vinegar to remove rust from metal. Vinegar works best on light surface rust rather than heavy flaky buildup.
Can baking soda get rust off metal?
Yes, baking soda helps remove light rust from metals when combined with vinegar or lemon juice. It also serves as a gentle abrasive when rubbed on the rust spots with a damp sponge or brush.
The abrasiveness of baking soda, along with the rust-dissolving citric or acetic acid, provides effective rust removal.
Is WD-40 good for removing rust?
While WD-40 helps displace moisture, it does not actually remove rust from metal surfaces. It may be able to loosen some surface rust flakes but is not an adequate rust removal solution. Acidic rust removers like vinegar, citric acid, naval jelly or commercial removers work better to get rid of rust.
WD-40 is good for rust prevention and lubrication though.
Summary
Rusting is an inevitable problem with metal cabinets with prolonged use, especially in humid conditions. But armed with the right rust removal techniques, you can fully restore your old worn-out cabinets back into functional condition.
The key steps are thorough metal preparation, use of appropriate acid solutions or abrasives to get rid of rust and application of rust-proofing primers and paints. With some time and effort, those corroded cabinets can once again become great assets in your home. Just be sure to take precautions when handling strong acidic rust removers.
Conclusion
Rust removal and prevention on metal cabinets requires a multi-step process – scrubbing off loose rust, degreasing the surface, removing remaining rust with acids/abrasives, completely drying the metal, sealing with primer and applying moisture barrier paints. The choice of rust removal method depends on the extent of rusting and whether the existing finish needs to be preserved or removed. With careful surface prep and the right rust remover, metal cabinets can be given a new long-lasting finish. Just be cautious when using acidic and abrasive products. Consistent care and maintenance is key to prevent recurrence of rust.Addressing rust issues promptly also avoids irreparable damage. With some diligent effort, your old rusty cabinets can be restored successfully to maintain their utility and aesthetics.