Cast-iron sinks can create a beautiful farmhouse aesthetic. However, since they're antiques, they may get rusty or discolored over time. Restoring one can be an inexpensive alternative to replacing it.
Keep in mind that cast-iron sinks can be very heavy, easily 100 to 200 pounds or more. You can remove it and take it outside to your yard to do the refurbishing. But since it's so heavy or you may not have an outdoor work area, you can also leave it in place and do the cast-iron sink repair there.
Use a wire brush to get as much of the old paint off. Wear gloves and a mask as protective gear as the paint may flake off as you brush. If there's any rust, remove that as well with the wire brush. If needed, you can use medium-grit sandpaper or a steel wool brush to scrub away rust according to the experts at Bob Vila.
Next, wash the sink out thoroughly. Any paint flakes and rust need to be cleaned off. If you wash it outdoors, you can use a hose as the water pressure works well to remove grime. After rinsing, allow the sink to dry. If there are remaining stains or rust, use one of the cleaning methods below.
Cleaning and Removing Rust
If your sink is rusty and dirty, there are several methods to clean the surface before painting. You can plug the sink drain and fill it with equal parts water and white vinegar. Allow the mixture to eat away at rust or other tough stains for one hour.
After an hour, see how much progress has been made. You can allow it to soak for up to eight hours, but after that, you run the risk of the vinegar damaging the cast iron, according to Bob Vila. After soaking, rinse the sink out with water. You can also spot treat instead by putting vinegar directly on a rag or towel and scrubbing the problem area.
Next, use liquid dish soap and steel wool to scrub away any remaining stains. You can also use medium-grit sandpaper. Baking soda and white vinegar can also be used to make a paste to scrub away stains. When finished, rinse the sink off with water and allow it to dry.
Another alternative is mixing Borax with water to make a paste. Wear gloves when cleaning with Borax, and apply the paste to any dirty areas of the sink and allow it to sit for several hours or even overnight. Wash it off and see if the Borax removed some of the staining. A Mr. Clean Magic Eraser can remove some tough stains on white surfaces as well.
If you still can't remove the stains, Lime-A-Way can be an excellent choice. It's very effective in removing limescale and hard water stains, as well as rust from antique tubs and sinks. Allow the gel to set for 10 minutes, then scrub until the stains are gone. Just be sure not to mix any of the cleaning products you use.
Apply Fresh Paint
The sink can be painted with an oil-based Rust-Oleum protective enamel paint in semi-gloss white, as well as other paints that can be used on metal and are rustproof, such as acrylics, oil or alkyd. Be sure to read the label or ask for help if you're unsure if it will stick to cast-iron and keep it from rusting.
Refurbished cast-iron sinks can look fresh and clean while keeping the antique style. Repainting costs considerably less than replacing a sink or tub. You can replace the handles and faucet to create an updated look.
Meg Scanlon earned a Masters from Johns Hopkins University. Her writing can be found on Hunker, Cuteness, Funny or Die, BarkPost, Taste of Home, LoveTV and ALittleBitFunny.com.