Just rinse it under running water, they say...

January 8, 2007 4:15 PM

Have I ruined my expensive blender by soaking it in washing soda?

I have a Bamix hand blender. A while ago I did not clean it immediately and it was hard to clean, so I put it in a bowl with washing soda (just like I do with pots and pans that are hard to clean) and let it stand for about a day. I now know that that was not a smart thing to do.

Now the "head" (the round thing you see on this picture) is a very dark grey, instead of the shiny metal color it was before. It seems like the dark gray is a layer on top of the metal. The inside of the head, where you put the blades, has white and at some places a bit yellowish stains. I cannot wipe this away.

What happened and more importantly: can I repair this?

posted by davar to home & garden (14 answers total)

Can you scratch into the discoloration with your fingernail?
posted by odinsdream at 4:28 PM on January 8, 2007

I do not see any difference when I scratch. Upon closer inspection I do see that there are quite a few very small "holes" in the dark gray layer. It is not as solid as I first thought.
posted by davar at 4:33 PM on January 8, 2007

I doubt that it is ruined - it should still work fine. You just have a layer of ugly corrosion on your head that shouldn't affect anything.

You can probably pretty it up with steel wool.
posted by MonkeySaltedNuts at 4:38 PM on January 8, 2007

Thanks MonkeySaltedNuts, I'll try the steel wool. It does not matter to me at all how it looks, but I worry that I now damaged the material and that that will leak into the food I am preparing (for my three year old daugher, among others). Is this unfounded?
posted by davar at 4:56 PM on January 8, 2007

First question, do you know if your mixer is aluminum or stainless steel? It's hard to tell from that photo. I think that washing soda reacts with aluminum.
posted by Kadin2048 at 5:17 PM on January 8, 2007

I had a similar thing happen on a garlic press I put in the dishwasher. Nature of the detergent unknown, but I usually use Cascade brand (sodium carbonate, sodium silicate, enzymes, surfactants). Turned the press kind of blackish, but it eventually returned to normal with wear and hand cleaning. I, of course, am probably doomed to an early grave for my chemical transgression.
posted by FauxScot at 5:33 PM on January 8, 2007

Washing soda (sodium carbonate) will indeed cause the corrosion and pitting on aluminum exactly like you observed.

Any corrosion that washes off into food is harmless (it's aluminum oxide, which is pretty darn inert), but unless you have it re-anodized it won't stay shiny anymore.
posted by oats at 6:30 PM on January 8, 2007

We have a bamix (actual bamix brand, assuming that's what you mean) and it's NOT aluminium. Steel with some chrome plating, I'm fairly sure. Have you tried wiping it with vinegar? If you do that, make sure you rinse it straight afterwards.
posted by polyglot at 7:26 PM on January 8, 2007

Funny, while I know you probably didn't apply power to it this might have something to do with your results.
posted by IronLizard at 9:02 PM on January 8, 2007

And I seriously doubt they made that blade from anything but stainless steel.
posted by IronLizard at 9:03 PM on January 8, 2007

I totally assumed it was stainless steel, that's why I soaked it just like I soak my stainless steel pans. It is just the head though, that's discolored, not the stalk that leads to it. The stalk (I hope that that is the correct or at least understandable word) is fine, so it appears that the stalk and the head are made of different materials. I agree that it seems unlikely that it is aluminium though, it sure "feels" like steel. Wiping with vinegar makes the white spots turn somewhat brownish.

It is an actual Bamix. I also contacted the company a few days ago, but I haven't heard from them yet.
posted by davar at 1:29 AM on January 9, 2007

Odd, perhaps they made it of high carbon steel? This is known to keep a better edge in the absence of corrosives. But then, being a food processor it should be expected to keep in contact with corrosives almost daily. Via (second link explains much if you're interested). Perhaps the blade has been subjected to a great deal of heat, which causes stainless to lose may of it's desirable anti-tarnish properties? Pictures would be nice and best sent to this forum. For a more knowledgeable audience, of course. I would have to say, though, that this probably poses no health hazard and should be fine unless it fails to operate correctly.
posted by IronLizard at 1:36 AM on January 9, 2007

Thanks IronLizard. I did blend soup with it, but not that often, and the blender is specifically designed to blend hot soups, so I doubt that that is the problem. It still works fine and I guess I'll start using it again and hope it improves like FauxScot's garlic press. If it doesn't, I'll ask the metalmeet people.

Thanks everybody!
posted by davar at 4:35 AM on January 9, 2007

When I say high heat, I mean has it ever turned orange hot? :)
posted by IronLizard at 4:43 AM on January 9, 2007