Stain Removal Tips for Cast Iron Bath Tubs

Kent Page McGroarty

Cast-iron bath tubs are made from a porcelain enamel surface being fused to cast iron under high heat and are an excellent addition to any finished bathroom. They are commonly chosen items during a remodeling process or for houses being built from the ground up.

A cast-iron tub that has been moved to the garden.

Molten liquid is poured into a mold, giving cast iron tubs their unique shape once the liquid hardens. These beautiful tubs also hold heat longer. Like any tub, they can develop rust stains as well as grease/dirt/soap scum buildup but are easy to clean if maintained.

Removing Soap Scum, Dirt And Grease

Soaps can leave residue that forms a type of scum.

Baking soda is a popular safe and natural method for cleaning the bathroom. Dilate baking soda with some warm water to make a pasty solution excellent for removing dirt, grease and soap scum from cast-iron bathtubs. One tablespoon of trisodium phosphate (TSP) substitute mixed with a gallon of hot water also will remove soap scum, dirt and grease, although this solution should not be used in combination with other cleaners. Avoid using scouring pads to remove dirt and soap scum, as such pads can cause tiny scratches on the tub's surface. These scratches subsequently can catch grease, dirt, hard-water deposits and soap residue. Cream-based cleansers also can cause additional buildup. Switch to a liquid, soap-free cleanser that does not contain soap to keep soap scum at bay.

Rust Stains

A very bad rust stain

Iron stain remover works well on rust. Abrasive cleaning powders are effective on rust stains, but take care when using such powders not to scratch the surface of your tub. Use the finest powder you can find and add water if using this method to avoid scratches. Pumice stones are rough, porous stones excellent for removing tough rust stains and other marks on your tub. Add some water to the stain and rub the stone over it, taking care to rub gently as to not scratch the surface. Be sure not to drop rust particles down the drain when cleaning because this can clog your tub. Keep the pumice stone wet and rinse it periodically so rust will not clog the stone. Once rust is removed, use lemons and salt on the stain. Pour salt over the entire stain. Cut a lemon in half and squeeze the juice on the salted stain and allow to sit for at least 24 hours. The rust will transfer to the salt and can then be washed down the drain without clogging it. Towel dry your tub after every use to avoid rust stains.

Other Tough Stains

Always wear gloves when dealing with chemical cleaners.

Chlorine or hydrogen peroxide bleach is an effective remover of particularly tough stains, though bleach will not work on rust stains. If using either of these to deal with stains, always dilute with water and rinse the solution off the stain after about two minutes. Acetic and muriatic acids can be used to remove some stains; however, acids will slowly wear down the porcelain enamel. Always rinse thoroughly with water if using acid or any chemical to clean your tub. Wear gloves when using chemicals to clean tub and wear rubber gloves if dealing with acid.