Dishwasher ruined shiny aluminum

A. Hi Laurie.
If you don't want to replace them, I think you can paint them with silver colored stove paint ⇦this on eBay or Amazon [affil links] . You may not find the perfect color but it should be pretty good. You may need a pin or toothpick if you get any paint blocking the holes.

Leave the exhaust fan on the first time you fire them up.

Luck & Regards,


Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

A. Metal polish; most likely you managed to oxidize the surface of the metal. Just use whatever metal polish you have handy to remove the surface oxidization, if you don't have any, try toothpaste.

Take the easy way out. Sneak out and buy an identical one. Rub it a tiny bit with toothpaste, give it to the lovely lady and tell her that you "polished it" No lie, but not the whole truth either.

P.S., keep this one in the hand wash category.

A. Try making a paste of water and cream of tartar ⇦this on eBay or Amazon [affil links] (available in the spice aisle at the grocery store, if not already in your kitchen cabinet). Use either a clean cotton cloth, or in this case, an old tooth brush, nail brush or sponge, and work the paste until the shine has been restored.

A. Dishwashing detergent is quite hard on aluminum pans that have not been anodized. They have an oxide layer that allows the pan not to corrode. Clean with a plastic sponge scrubber in warm water, coat the pan with a Light coat of oil and bake at 350 °F for an hour or so. Let it cool down in the oven. Should work fine.

A. Marjorie,
Aluminum is sensitive to harsh detergents. Most dishwasher detergents are alkaline in nature. The good news is, the white spots can be removed. Buy a small jar of cream of tartar ⇦this on eBay or Amazon [affil links] in the spice section of the supermarket. Mix in a small amount of warm water to form a paste. With a medium coarse rag rub the paste over the whole pan in a circular motion giving added time to the white spots. Rinse well with warm water and towel dry. You may have to repeat the process. I would use a mild dish detergent and wash pans by hand from now on.

A. Hi Marjorie,

This sounds like the aluminum was oxidized during the wash phase. Are you even supposed to put aluminum in a dishwasher?

Okay, so here's what's happening:

Your dish-washing detergent contains alkaline phosphates. At high pH, the 'passive' aluminum surface dissolves as Na2Al(OH)4 (sodium aluminate). This reveals 'active' metal underneath, which reacts with the phosphates in the water to form aluminum phosphate. Sodium aluminate reacts with sodium phosphate to form sodium aluminum phosphate. Sodium aluminum phosphates precipitate out of the water, and deposit onto the sites along the surface of the aluminum cookware, leaving these powdery spots.

Sodium aluminum phosphate isn't dangerous if you accidentally consume. It's often used as a leavening agent for baking. If you scrub the surface with a Brillo ⇦this on eBay or Amazon [affil links] pad, this should be fine to use again.

In the future, try to clean baking sheets by hand; dishwashers provide a corrosive environment for aluminum.

A. The aluminium that the cake tins are made from is probably being attacked by the dishwasher powder. This is starting to cause corrosion which is the white spots. My advice would be to clean the tins with some of the more abrasive pan scourers to remove the corrosion, rinse well. Put a light coating of vegetable oil on the pans with kitchen roll before putting them back into your cupboard. From now on only hand wash them.

A. Hi, Tawny

I think it's safe to use, and I believe if you look it up in authoritative places you will find the same opinion expressed by the Alzheimer's Association, EPA, etc. But that black smut is unappealing and if you can get rid of it temporarily, do it.

I used your inquiry as a teachable moment for myself, taking an old aluminum ice cream scooper that has been in the dishwasher a hundred times and seeing what I could do with it. Rubbing it with a cloth soaked in vinegar ⇦in bulk on eBay or Amazon [affil links] took off loads of the black smut, but was generating it almost as fast as it took it off :-)
After I rinsed it, not much further black smut came off, and it was darker in color because I had dissolved any white corrosion products. I then tried a sulfamic acid metal polish and the experiment went pretty much the same. Not having any Mothers Mag & Aluminum Polish ⇦this on eBay or Amazon [affil links] at hand, I tried rubbing compound ⇦this on eBay or Amazon [affil links] (by hand), and the result was slightly better.

Moving on to conjecture, I think you could brighten it up and remove the black smut if you buff it with a power tool (a buffer ⇦this on eBay or Amazon [affil links] , a Dremel ⇦this on eBay or Amazon [affil links] , or at least a buffing pad ⇦this on eBay or Amazon [affil links] on a battery operated drill ⇦this on eBay or Amazon [affil links] ) and the Mother's. But I think once the anodized coating is gone, it's gone, and it won't stay shiny for long. Sorry.

Regards,

"The Surface
Treatment &
Finishing of
Aluminium and
Its Alloys"
by Wernick, Pinner
& Sheasby

(note: this book is two volumes)

on eBay or

AbeBooks

or Amazon

(affil links)

A. It has been a while since I've read through it, and I don't have my copy handy, but I recall Wernick Pinner and Sheasby ⇨
stating that you could get really good corrosion resistance by submerging aluminum in boiling water for 24 hours but that it wasn't economical for most manufacturing purposes. In this case however, if you CAN brighten it back up (even temporarily), if you have a way to boil it for long enough it MIGHT stay that way. Mind you, I've never personally tried it.

Good Luck!

Great idea, Jim, thanks!

Readers: I see graphs in that book showing that the oxide film does continue to grow for 16 to 24 hours in boiling water before it tops out. Some other pages seem to indicate that deionized/distilled water is very important, so try boiling in a very clean enameled pot (or a pot lined with a pot liner or at least a plastic bag), and maybe change out the deionized/distilled water a couple of times.

If anyone tries it, please let us know how it goes :-)

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

A. Hi, Cat.

I'd guess that the pink/purple/green tinge is a diffraction pattern caused by the very thin last of the anodized coating (sometimes you see automobile headlights shifting color as they approach you if they have anodized reflectors). With a ruined pot, this sounds like the perfect time to try Jim's proposed cure of boiling distilled water in it for 24 hours. Please let us know what happens!

Regards,

A. There IS hope for dishwasher discolored aluminum items. My beautiful Arthur Court Measuring spoons were accidentally washed in the dishwasher. I researched on-line and decided the "least likely to do more damage" approach would be the Brillo pad ⇦this on eBay or Amazon [affil links] solution. IT WORKED! I rubbed & scrubbed with a blue filled pad until they were covered in blue goo. This is going to take serious rubbing! Then I used a soft bristle brush & warm soapy water to briskly brush them repeatedly to remove all tarnish and blue goo. I used a little more dish detergent & clean warm water to brush them again and rinsed in warm water. Then I dried them with a soft clean towel. Never underestimate a Brillo Pad & elbow grease! Amazing! I am submitting photos.

A. I sought this site because of discolored aluminum.

After reading some of the answers I picked up the sponge that I had just used with a preparation to clean my glass stove top. I spread it on the 50 year old "Wearever" Aluminum chicken fryer that had belonged to my mother. To my surprise, when I came back 10-15 minutes later, a lot of the discoloration was removed, I applied more and let it sit with a good result. Now I am treating the bottom of the pan.

It is identified as Weiman Cooktop Cleaner ⇦this on eBay or Amazon [affil links] .

I haven't tried my cake pan yet.

Discolored aluminum cake pan
This is an endorsement to Karen Kettleson's post dated 2/26/15. Weiman Cooktop Cleaner ⇦this on eBay or Amazon [affil links] applied with a scouring pad and wiped off with paper towels did the trick for me. It took three passes but the pan was very heavily stained and is nearly spotless now. Note: please wash off the cleaner thoroughly before using your cookware. Thanks for posting, Karen.

Affirming the use of cooktop cleaner. The brand I used was Cerama Bryte ⇦this on eBay or Amazon [affil links] and it almost completely restored the aluminum lid to my coffee urn. Yay!

A. Used Cerama Bryte ⇦this on eBay or Amazon [affil links] and yellow scrubber that came with it and it removed all the white residue and most of the black from my cookie sheet. Thanks for the glasstop cleaner tip.

A. Based on other suggestions here, I used #0000 steel wool ⇦this on eBay or Amazon [affil links] and glass stovetop (paste) cleaner, and it completely restored knives and other pieces that had been "ruined" for years.

A. I was bummed to find my retro cake cover discolored from putting it in the dishwasher. Found the recommendations here and modified (can't help it, I'm a guy) some of the suggestions and results were spectacular.

I took damp paper towels folded X3, wrapped them around the cake cover; drizzled white vinegar ⇦in bulk on eBay or Amazon [affil links] atop the cover to seep into paper towels then put it in plastic shopping bags to soak. Removed them and made a paste out of Barkeepers Friend ⇦this on eBay or Amazon [affil links] and water and scrubbed some with a scrub sponge.

Cleaner than it's ever been. Still some slight telltale signs of discoloration but I'm a happy guy; my cake won't go stale.

A. Try Barkeepers Friend ⇦this on eBay or Amazon [affil links] . I made a paste and rub most of the grey off easily. soaked in water with some of the barkeepers friend for about 10 minutes, grabbed a scotch brite pad and with very little effort in less than 2 minutes it was like new.

A. I read many of the responses, then combined all the knowledge gathered, along with what I had on hand, and discarding anything remotely dangerous, I came up with an amazing result. I tried it again & again with the same results.

My dishwashing disaster was a very old aluminum sieve that I loved. Here's what I did: I applied Barkeepers Friend ⇦this on eBay or Amazon [affil links] , smeared it around with a folded wet paper towel, and let it sit for 5-10 minutes. Then I used the same wet paper towel to rub briskly back and forth over the area. I rinsed it well and the area was cleansed of the blackish mess! But it wasn't bright, as noted by others that had used that technique. But here's what I did differently: I topped it off with a very light rub of Brillo. Now it was shiny! And it didn't take hard and lengthy scrubbing/rubbing, and no scratches. (The scratches in my photos go back many years)

A. Hi Ken. You're sure they are stainless steel rather than aluminum? I'm very surprised that a dishwasher would have such an effect on stainless steel cups. Stainless flatware goes into hundreds of millions of dishwashers every day. But if they are aluminum, this page is full of ideas for you :-)

Regards,

? Hi Martha. I've heard of dishwashers damaging aluminum but I've never heard of aluminum damaging a dishwasher. Can you point us to any reference that leads you to believe this is the cause of the blackening? Are the surfaces in question plastic, or stainless, or what? Thanks!

Regards,

A. Hi Kathy. The kind of reaction you are envisioning is electrochemical, and can only happen when there is actual physical contact (electrical continuity) between the aluminum and the stainless.

Whether the problem was some other stainless item touching the pan, a change to a more alkaline dishwasher detergent, or just gradual wear of some clear coating on the cake pans, or the higher temperature than newer dishwashers usually use, the thing remains: aluminum doesn't belong in a dishwasher which is using the conventional extremely alkaline dishwasher detergents; they destroy aluminum regardless of any other factors.

Regards,

A. I just tried all the above suggestions on a formerly shiny, now tarnished, aluminum bowl. Forget the glass top cleaner, the lemon & salt, the lemon, the vinegar ⇦in bulk on eBay or Amazon [affil links] & baking soda.

After wasting 1 hr scrubbing, forget everything except: in a large pan add water & cream of tartar ⇦this on eBay or Amazon [affil links] (I did about 2 T); heat to just below boiling; let pan/bowl/item sit until color changes to normal -- about 30 minutes. If you have a large bowl you will need to rotate it as the color changes. It's a lot easier than scrubbing for a long time.

A. Hello,

A video on the laziest method to clean aluminum after dishwasher, no scrubbing needed -- Oven, roasting pan, and cream of tartar ⇦this on eBay or Amazon [affil links] .

Enjoy!

A. Hi I have a SMEG oven and decided to put the burners in the dishwasher. After 10 mins they looked like they were ruined. I searched to find a way to rectify this - I tried vinegar, coke, polish etc. Nothing worked until I found Silvo tarnish guard ⇦this on eBay or Amazon [affil links] . I polished for ages and voila they are shining again. I am in England if that makes any odds

A. Have similar SMEG cooker with similar burners which also turned black in the dishwasher. A Brillo pad ⇦this on eBay or Amazon [affil links] removed this and restored back to a shiny finish in minutes.

A. Try ammonium citrate 5% pH 7 solution (dissolve 50 gms citric acid ⇦this on eBay or Amazon [affil links] in 1 lit water and add some ammonia ⇦this on eBay or Amazon [affil links] until pH is 7). Hope it helps and good luck!

A. My experience with Cascade Platinum ⇦this on eBay or Amazon [affil links] is that it takes off the metal from utensils and pots & pans, and makes spoons black. I have no idea what causes this, but as far as a dishwasher detergent, it's the best out there and works exactly how they describe it. So keep the metal out and you will be okay.

A. Hi Richard. I have a Bosch dishwasher with stainless interior as well, but we don't put aluminum in the dishwasher; it's just a bad idea. Personally I don't think the stainless interior is the problem, but you may be on the right track with the water temperature. Maybe you can turn down the water heater as long as the clothes washer keeps working.

Regards,

A. With more research and a bit of experimentation, the appearance of aluminum corrosion with a new dishwasher can likely be attributed to a combination of:
previous removal of phosphates (which had some protective effect) from dishwasher detergents;
the addition of more corrosive agents to detergents to make up for the missing phosphates;
the higher water temperature of the new dishwasher;
the higher concentration of detergent in a more water-efficient dishwasher;
and the longer contact time of the new dishwasher.

Switching from Cascade Platinum (15X) to plain old Cascade (10X) helps a good deal but does not eliminate corrosion. Aluminum-clad pots will have to endure it; the rest of the aluminum will be replaced with stainless steel.

A. Hi Matt. Sorry about that. The manufacturer should probably have warned you. I personally like the cream of tartar ⇦this on eBay or Amazon [affil links] answer the best if the grinder is made of aluminum (I think most are actually steel or iron with tin plating -- check it with a magnet).

Regards,

A. Hi Dorothy. I am not familiar with the use of ketchup on aluminum (cream of tartar seems the most highly suggested fix on this site). But if the ketchup solves the problem, great. There is no need for aluminum to be shiny for it to be safe and usable. Good luck with it. However, again, are you sure those parts are aluminum rather than tin-plated cast iron or steel?

Regards,

A. Hi Thomas. You directed your question to Matt, who was speaking of his new meat grinder, and it looks like you are referring to a meat grinder as well? The problem here is that you/he/we seem to be assuming these grinders are made of aluminum, such that the procedures used for repairing aluminum finishes should be used -- but I don't think they are :-)

Does the weight of your unit lead you to believe it's made of aluminum (aluminum is 2-1/2 to 3X lighter than most other metals). Have you checked it with a magnet to make sure it's not cast iron or steel? Was it originally a shiny chrome-like look (perhaps stainless steel), or was it a softer, very slightly whitish or slightly yellowish color (perhaps tun plated)? I am not certain, but I believe most older hand-operated meat grinders were actually made of tin-plated cast iron (tin plating is not only corrosion resistant but extremely food-safe). That might be what you have. If so, I think you'll find topic 5106 more informative and helpful than this one about aluminum.

Luck & Regards,

A. Hi James.
Hundreds of millions (if not billions) of people have boiled water in aluminum and/or stainless steel for many generations, so it's certainly 'food safe' as far as most people view it (some, of course, feel that cooking in aluminum pots or high quality stainless is dangerous).

Although it is not impossible to do sulfuric acid anodizing at home, this is a multi-step process involving acquisition of equipment, chemicals, and knowledge that you are not going to want to learn, practice, and do for the sake of a pot or tumbler or two.

As for "has anyone done this successfully", no one has responded in this forum yet, but this is the back story: Aluminum is a very active metal that oxidizes instantly, automatically leaving a very thin oxide coating on the surface. Sulfuric acid anodizing is an approach that employs electricity and acid to engineer that oxide coating to maximum thickness, utility and corrosion resistance. Boiling in D.I. water for up to 24 hours is a compromise between doing nothing and sulfuric acid anodizing.

I think authoritative sources like Wernick Pinner and Sheasby indicate that it can be of some value and that the thickness will continue to build for up to 24 hours. It's perhaps possible that scholar.google.com might locate a controlled study if you're more patient than me, but the book you referenced is internationally accepted by professionals in the aluminum treatment industry as the absolute authority on aluminum treatments :-)

Regards,

A. There are many chemical oxidation processes for aluminum; try USPTO gov website (expired patents). Sodium aluminate, potassium ferricyanide, ferric citrate, or potassium permanganate and calcium hydroxide based are just some of them ... Hope it helps and good luck

A. Hi David. The Q&A immediately above yours seems applicable. This site has, without exaggeration, hundreds of references and opinions covering both sides of the question of whether aluminum is safe. Please search the site with the term "safety of aluminum" if you have time to spend on the question. If not, all I can say is some people (including me) think it's safe, based largely on the fact that hundreds of millions of families have cooked with it for generation after generation and no 'smoking gun'; some think it's not safe and you'll even find "aluminum-free" underarm deodorant for sale.

Regards,

A. Hi Vanessa. When you mention "rust" the first thing we need to confirm is that you're talking about aluminum because it can't rust -- it can never get that orange-brown stuff because there isn't any iron in it to produce rust. Please test with a magnet because aluminum is non-magnetic.

I suspect you have a tin-plated steel pan, but let's confirm aluminum vs. steel part first. Trying to figure out how to repair a material by following instructions for repairing a different material is to follow the will-o'-the-wisp into the marsh :-)

Luck & Regards,

A. Hi Linda. It's safe enough to suit me and many others, but some people think any aluminum at all is unsafe -- the deodorant shelf at the drugstore now has brands prominently labeled "Aluminum-Free!"

Please see discussions of aluminum safety on thread 8962 or 22551. Good luck.

Luck & Regards,

Thanks, Ted! I'll try both strings you mentioned. Take care...

A. Unfortunately you don't. Unless you have new pots with specially designed coatings labeled as dishwasher-safe, the alkalinity of dishwasher detergents will tarnish them or worse.

Luck & Regards,

A. For aluminum discolored by running thru the dishwasher I've had good luck with a product called Whink Rust Stain Remover ⇦this on eBay or Amazon [affil links] . (1.5-3.5% hydrofluoric acid). Use the non-scratch abrasive dish sponges (the blue or white ones) and apply a little bit, it doesn't take much, and rub gently. I'll then rinse, apply some Barkeepers Friend ⇦this on eBay or Amazon [affil links] , make a thin paste and rub gently with the same non-scratching sponge for a couple minutes or you can let it soak and come back after a few minutes for a rinse, re-wash and dry.
Try it. You may be surprised.

Hydrofluoric Acid


"HF burns, not evident until a day after"
by Dr. Charles Eaton
(http://www.handcenter.org/resumee/resumee.html)

A. Hi Andrew.

Whink contains hydrofluoric acid (HF), as you mentioned. Concentrated HF is life threatening, and although the concentration in Whink is quite low, I urge readers to get the Safety Data Sheet for Whink and to fully investigate HF's hazards before using products which contain it. At the least, wear disposable latex ⇦this on eBay or Amazon [affil links] or nitrile ⇦this on eBay or Amazon [affil links] gloves; personally I wouldn't use HF in any concentration without calcium gluconate neutralizing gel ⇦this on eBay or Amazon [affil links] on hand in case there is skin contact.
Luck & Regards,


Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

A. Hi Paula. I think it's actually the same problem, i.e., loosely adherent oxides. I think the cream of tartar scrub will solve the problem, and thereafter only hand wash it.

Luck & Regards,

A. Hi Jennifer. Dishwasher detergents are strongly alkaline, and aluminum cannot take that alkalinity. As you can see from this l-o-n-g page, you're far from the first to have put aluminum in the dishwasher.

My feeling, from my own experience and having read a lot of postings and watching a number of videos, is that the cream of tartar ⇦this on eBay or Amazon [affil links] polishing is the most reliable solution, but you might try a Brillo pad as suggested by Amber M if you have one handy.

Luck & Regards,


Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey