Cast-iron bathtubs and sinks were a common fixture in older homes, yet their unique vintage charm means we're seeing them pop up in many newer remodels. Unfortunately, years of use or neglect can make for one discolored and dingy tub or sink! Here are a few tips to keep the porcelain on your antique fixture looking next to new.
What You Need
• Liquid dishwashing soap
• Ammonia
• Baking Soda
• Lemon oil
• Table salt
• Lemon
• Old rag
• Nylon or soft sponge
• Bucket
Instructions
1. Cast-iron is traditionally covered with a porcelain enamel that's fused to cast-iron in a furnace. While porcelain is a highly durable surface, it's susceptible to chips, cracking and dulling of the finish. If you use the wrong products, you will accelerate the degradation of the surface, so let's begin by talking about what not to use. Abrasive cleaners such as scouring powders, white vinegar (or other cleaners with a high acidic content), and steel wool should all be avoided, as they can damage the finish. For the best results, always start with the gentlest cleaner and work your way up to more powerful applications. Remember, proper care will simplify ongoing maintenance.
2. For gentle weekly cleaning, mix 2 tablespoons of dishwashing soap containing a grease cutting agent with 1 gallon of hot water. Use a soft rag or sponge to dip into the soap mixture and scrub the tub or sink. Rinse well.
3. For monthly or deep cleaning (when moving into a new home or cleaning up a newly purchased vintage tub or sink), pour warm water into a bucket and add 1/4 cup of baking soda and 1/4 cup of ammonia. While baking soda is slightly abrasive, it's mild and generally safe to use on porcelain, while ammonia cuts grease and soap scum buildup.
4. Soak a non-abrasive sponge in the baking soda/ammonia solution. Scrub the surface of your porcelain bathtub or sink, paying particular attention to stained areas.
5. Dip the sponge in the solution, scrub and repeat until you're satisfied.
6. Rinse well.
7. After rinsing, wipe thoroughly with a clean rag or the baking soda will leave a white film behind.
8. As a last resort, mainly for tough-to-remove rust stains, cover the stain with table salt. Take half of a lemon and squeeze the juice over the salt. (I have also heard cream of tartar and lemon juice works, but have never tried it). Scrub the salt/lemon mixture with a clean cloth or a nylon sponge. If the stain still doesn't come up, leave the paste-mixture on the stain for an hour or so. Squeeze more lemon juice on the stain and try scrubbing the stain again, then rinse and wipe clean.
9. To add shine and a protective coating, squeeze a small amount of lemon oil onto a clean rag and rub the lemon oil into the sides of the porcelain bathtub or sink, avoiding the bottom of the tub to prevent slipping. The lemon oil will help repel soap scum and other dirt to keep the sink/tub clean longer, and it smells good, too!
10. If none of these suggestions work and your tub or sink still looks a bit lackluster, it might be worth the investment to have your fixture re-glazed by a professional. While there are DIY re-glazing kits on the market, the results are usually shoddy and do not last. Unlike fiberglass or acrylic, your cast-iron fixture can stand the test of time, so it's well worth the expense to hire a specialist for the job. Keep in mind, this doesn't run cheap. I was quoted around $500. While if properly cared for, it should last for many years, the finish will not be as durable as the original porcelain finish. Re-glazing, done in your home by a professional, is not a duplication of the tub's original porcelain dip-coat, but actually a specially formulated gloss paint. In some cases, you can send a valuable cast iron tub off-site for a new dip-coat, but this is usually extremely pricey.
Additional Notes:
- Bathtub rings can usually be blamed on oily bath products or a clogged drain. If you use a bath oil product, make sure to do a quick cleaning afterward and keep the drain clog-free.
- It's always wise to test a small hidden section first to ensure that the cleaner will not cause any adverse effects to the surface of the porcelain.
(Images: Kimberly Watson)
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Great info. Just fyi for anyone reading, I just learned recently that old cast iron tubs often test positive for lead. I am planning to test my bathtub, so wanted to pass the info along.
Watch the kitchen salt! It can scratch. The reason those old tubs became so dingy in the first place was that they were cleaning with abrasive in the first place. I use liquid dish detergent on mine with a nylon net thingy and swish it round after each bath and it stays sparking.
I didn't think you were supposed to mix baking soda and ammonia because it put off toxic fumes when mixed. Or is that ammonia and vinegar?
my tub has been painted with tub paint and its slowly chipping away. whenever i scrub the tub or shower more comes off. i heard a tub should only be repainted professionally and i doubt my land(slum)lord will pay for it. is there a porcelain safe way to remove the paint?
OR, you could pour Clorox Toilet Bowl cleaner all over the surface, wait for the green to turn white, and then rinse.
I recently moved to a condo with an original porcelain kitchen sink. Unpacking the groceries, the toilet bowl cleaner fell in the sink, popping open in the process, and left a white line across the sink. I was shocked. It worked great. The sink looks brand new. And once I got the clean deeply clean, now I just clean it with a Clorox soak once in a while.
It's more than a little weird to use a toilet cleaner on a kitchen sink, but the bottle did not go back and forth.
ButterfluyBleus, I think you're thinking bleach + ammonia, which makes toxic chlorine gas.
I love the lemon oil idea! Does anyone have a similar suggestion for a stainless steel sink?
ButterfluyBleus it's ammonia and bleach that you are not suppose to mix.
Also, DO NOT USE BLEACH. If you do, and it ends up turning your bathtub an ugly brown/yellow color, pour hydrogen peroxide over the stains and they'll disappear, almost like magic. Might need a light wipe with a cloth, but shouldn't need scrubbing.
Great info - I didn't know about that lemon oil trick...
...I bet it would work well in a kitchen sink too!
Will the AT mavens also post suggestions for maintaining fiberglass and acrylic tubs & liners?
"I just learned recently that old cast iron tubs often test positive for lead."
Why would it matter - Were you planning on eating your tub?
The trick for my 70+ year old white porcelain tub and sinks has been the magic eraser. They were very dingy, stained and paint splattered. After taking a razor to the paint, and using lots of the above mentioned techinques, I still wasn't happy with the results. But using a magic eraser every week as part of my usual cleaning routine has slowly taken out the deep stains, and has given the surface a lovely luster. Perhaps it's damaging the porcelain, but when I leave this apt, it will be gutted and these fixtures will end up in a trash heap, so I'm not overly concerned. They look much better!
@Village: if you don't mind supporting Clorox and having your food and dishes swim with Clorox Toilet Bowl Cleaner residue, sure. All this fuss about making things "sanitary" at the expense of not making them poisonous!
@bepsf: you'd be amazed at what can be absorbed through your largest organ.
I don't put food or dishes in the sink. I have a dishwasher. The sink is mainly used to wash my hands. But I get your point. I don't like Clorox around food either. I only used one bottle to get the sink pearly white, and I haven't used it since.
I have used Hydrogen Peroxide to clean my drains for years, but it never occurred to me to use it to clean the porcelain as well. I'll give it a try.
I used to have a double 18/8 stainless steel sink that I loved. I cleaned it with Arm & Hammer Degreaser, and then polished it with Sterling Silver Silver Polish, which also works on stainless.
Barkeepers friend is the best, and not too harsh.
So someone painted (or tried to refinish, poorly) my cast iron tub. I've been trying to get all the paint/crappy refinish off since I moved in, but recently it's been flaking off like crazy (but remaining stubbornly in large places when I try to scrub). Any recommendations?
My cast iron tub is chipping too. I'm thinking of using this product : http://www.vintagetub.com/asp/product_detail.asp?item_no=VT-1
However, the surface underneath the chips looks just fine and I'm wondering what if I peeled it all off... I have no experience with a peeling tub. Does anyone know what lies underneath the porcelain finish and why I can't just peel it off and leave it like that?
The thing about bleaches, including hydrogen peroxide, is that you're not actually getting the dirt up, you're just turning it white. Both reducing and oxidizing bleaches result in a shining white surface that isn't really all that clean, and which can actually turn back to the original color over time. (Bleach a piece of vintage pottery in hydrogen peroxide, put in on a shelf, and wait a few years. The stains will usually reappear eventually. It's all still in there.) And be particularly wary of chlorine bleach in metal tubs--if the finish is pitted and porous, you could cause a major rust problem.
Does anyone know where you can get the metal tub shelf that extends across the tub in the first picture? I really need that!
Bobby Heugel - This is where I bought the bath caddy from. https://www.mxyplyzyk.com/v03/index2.php?cat=200
Isn't borox supposed to be a pretty good cleanser for porcelain-coated fixtures?
Another request for tips on removing the finish of a badly-refinished tub! Mine started peeling off in big sheets (it was re-glazed by the previous owner) but does stubbornly stick in other places. I've worked on it with a razor, but that leaves marks that then won't come off with scrubbing. I've pretty much given up in hope of the day when I can replace the tub altogether. I love the old vintage tub, but I think replacement may be inevitable.
i second the Barkeeper's Friend recommendation. it's a little abrasive, but totally worth it for a serious job. for me it worked like a charm to remove residue from those tub stickers (thanks to the previous owner) that i'd been unable to remove for 10 years.
So what do you do if you have spots in your tub that seem to be unfinished? We have a spot in ours that is yellow and no longer smooth like the rest of the tub... I've tried scrubbing it(I though it was just a tub ring, but for the life of me I can't get it off of there)
...having your food and dishes swim with Clorox Toilet Bowl Cleaner residue,...
(emphasis added)
Because whoever uses this stuff isn't going to bother to rinse it away?
The biggest health risk from bleach (sodium hypochlorite) comes from inhalation. If you use it, don't use it full strength, and use it only in well-venilated areas.
Bleach is an extremely effective disinfectant against all kinds of bacteria. Practically all commercial kitchens routinely use it to disinfect work areas. Even bars use it to clean their glassware. And don't get me started on slaughter houses and packing plants (where bleach is often used to disinfect meat!).
I can't comment on how safe bleach is on porcelain, but just felt the need to defend it's practicle appliacations and to point out how widespread it's use is.
I just tested my old cast iron tub for lead and it tested positive. I've checked with two doctors who say that you probably can't absorb lead through the skin, but it is bigger concern if you've got toddlers who put their wet hands and toys in their mouths. Just a heads up.
I just had my clawfoot tub reglazed for 350. It looks wonderful. But before that... The thing that removed the stains that looked like they'd never come out was... Toothpaste. It took alot of elbow grease but it really works. : )
Kaboom works great on soap scum. I've used toilet bowl cleaner too. both work well.
Wipe your porcelain tub with dry cloth every after use to prevent the formation of water stains and soap scum. Using abrasive cleaners will make it less stain-resistant. To remove those hard to remove rust stains, it would be best to use a 'green' commercial rust remover.
Another tip? Try grapefruit and salt. Scrub a dub-dub, and you've got a clean tub.
More tips, tricks, and trends at sink.com.
I have a new porcelain sink and i have pot marks or metal marks on it.
They are small, but I want them gone. Please HELP!!!!!!!!!!!!!!!
We bought a house where the tub was in good shape on the sides of the inside but the finish on the bottom of the inside was worn off to where it was porous and felt like sandpaper and would absorb rust, stains, etc. I don't know if the previous owner etched it on purpose or by accident. We were going to replace it, but then I decided to try this stuff called Bath Brite. Here is their website: http://www.superjetco.com/. I think it worked pretty well. First I cleaned the tub with normal cleaners, then got rid of rust stains using the grapefruit and salt paste someone recommended online here (which works awesomely). Then I only applied the Bath Brite process to the bottom inside of the tub, which is not what they recommend, but it came out fantastic in my opinion. They send you three bottles--one of cleaner, which I used only gently and briefly once over since the tub was already clean. Then I put on 3 layers of the "Step 2" using the included sponge and then 3 layers of step 3 to make it shine again. It doesn't look quite as glass-like as newly finished porcelain, but it is shiny, white, clean and smooth and it is holding up like it was always finished. It might be worth a try before you replace your old tub or before you get it professionally re-coated. Once you do that this stuff won't work anymore they say. I have a baby so I didn't want fumes or dangerous chemicals in the house.
DIY bathtub refinishing kits dont work period. The article was pretty spot on regarding cleaning a bathtub thats in good condition with the exception of the salt and lemon thing (lemon has acid and salt will scar the surface). If you just cant clean your bathtub or it has chips, holes and pitting i suggest bathtub refinishing by a professional. It really is your only choice when dealing with a clawfoot tub. I have posted a video of the Bathtub Refinishing process on my website. I realize this post is old but you never know!