Salt in vinegar and a stainless steel scrubby will dissolve rust. Dry, then apply touchup to a warm tub.
While the best cleaner for cast iron tubs is a mild soap, other products are effective but have slightly higher risks. Ammonia, for instance, removes soap scum but is a harsh cleaner and requires you to wear gloves. Pro tip: Never combine ammonia and bleach.
The simplest and safest option for removing rust stains is to use oxalic acid. Depending upon the location of the rust stain, you can choose the right option from the following. You can sprinkle the rust stains with oxalic acid and then sprinkle with water if it's on the bottom of the bathtub where this is feasible.
You need something abrasive to get rid of rust residue, but still, you need to scrub hard for desired outcomes. If you don't have time for scrubbing, then use a magic eraser. All you need to do is to swipe it with the magic eraser on the affected surface. This will break down the rust residue and make your work easier.
Use WD-40 as a Rust Stain Remover
That is why we want to recommend using WD-40 Multi-use Product. It is suitable for almost all surfaces and is the best rust stain remover on this planet.
The process involves sandblasting off the old finish, then baking on a new enamel coating at 1,475 degrees Farenheit for about four hours. “It's genuine porcelain enamel, the same glass coating used on bathtubs you buy in stores,” says owner Kara Kopplin.
It is also unwise to use acidic products on the enamel surface of a Cast Iron Bath. Using products ranging from vinegar to specialised bathroom cleaning products - which some people would use for an acrylic bath - wear away the enamel.
Cast iron needs to be cherished, and rust is the enemy. The easiest and fastest way to remove rust from cast iron is Evapo-Rust®. It will spare your knuckles, as there is no scrubbing with brushes or steel wool involved. It is also safe to use on your cooking supplies.
WD-40 can be used to remove rust from your cast-iron stovetop depending on how much you use and how long you leave it there. If you want to get rid of it quickly, you can try adding more WD-40 or applying the same layer over again.
We do not recommend using CLR on cast iron. CLR can compromise the metal.
Remove any rust and get down to bare steel. Apply a couple of layers of fiberglass cloth soaked in acrylic resin from both the bottom and top. Sand the top surface and apply some appliance paint. This will probably last 3 to 5 years.
Use Vinegar And Baking Soda
Mix the vinegar and baking soda in a ratio of 1:3. Use an old toothbrush to apply the paste to the rust stains in tubs, sinks, and toilets. Let it sit for one hour, scrub it with a sponge, and rinse.
Resurfacing materials for a porcelain or cast iron tub usually cost $350–$600, while fiberglass can cost $300–$1,000. Adding enamel can tack on another $350–$600.
Compared to the acrylic bathtub, it can cost you two times of standard bathtub cost. But this can be considered as a good investment since cast iron tubs offer great durability and last longer.
It's important to not use anything too aggressive such as steel wool, sponges or other abrasive cleaning methods as these will strip your seasoning. For particularly difficult to clean messes, fill your pan halfway full with water and heat over the stove.
Mix warm water, baking soda, and ammonia in a bucket.
Ammonia will remove soap scum while the baking soda will wash away grime without scratching or damaging your cast iron tub.
if you have a fiberglass, cast-iron, porcelain, or acrylic bathtub give these two products a try Bar Keepers Friend and a Pumie scouring stick do a great job at cleaning these types of bathtubs!
Baking soda and vinegar combine to make a fast and easy rust removal solution. Vinegar is a versatile cleaning agent, and the acidity will help dissolve the rust. Adding three parts lightly abrasive baking soda to one part vinegar can really help scrub away those stains.
WD-40 Specialist Rust Remover Soak.
To remove light rust, leave parts in the solution for 1-3 hours. To remove heavy rust, leave parts in the rust removal solution overnight. Do not use on parts that have bluing, browning, or protective oxide paints, as those protective coatings would be removed.
Shields recommends the product Whink Rust Stain Remover for cleaning tubs. "This stuff comes in a goldish-brown bottle and works like a charm because of the acid-based formula," she says.