Cast iron is strong and durable. Its various uses include pipes, machinery parts, buildings and bridges as well as everyday cast-iron cooking skillets. Cast-iron bathtubs usually have a porcelain enamel surface that's acid resistant. But over time, using the wrong cleaners can cause pitting and scratches and trap dirt in the porcelain. Employ safe cleaning techniques to keep your cast-iron tub looking good for a long time.
Vinegar and Baking Soda
Either use a spray bottle filled with white distilled vinegar or pour the vinegar directly on the tub's surface. Then, sprinkle baking soda evenly over the vinegar. Using a no-scratch scrub brush or sponge, apply pressure and scour the bathtub as the mixture foams. Let sit for a few minutes, then rinse with hot water. These cleaning materials are also environmentally friendly.
Wet a stain-erasing sponge, such as Mr. Clean Magic Eraser, and squeeze out excess water. Apply pressure to the sponge, scrubbing the bathtub surface and concentrating on stubborn stains. Rinse the bathtub with hot water after cleaning.
Bathtub Scrub with Bleach
Apply a no-scratch bathtub scrub with bleach, such as Soft Scrub with Bleach, to a no-scratch sponge. Using a circular motion, rub the sponge over the bathtub's surface, concentrating on stubborn stains. Let sit for a few minutes, then rinse the tub with hot water.
Another gentle cleaning method involves mixing one tablespoon liquid detergent (such as Dawn, Palmolive or Joy) with one gallon hot water and using a no-scratch sponge to wipe the surface of the bathtub. Rinse with hot water.