Black and brown colored spots on knives

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SOS pads do not have the acid that you need to remove the oxidation from the stainless steel knife blades. Remember that to remove an oxide, you need to set up a reduction reaction. The acid will break the bond between the iron and oxygen amd make the stains disappear. One thing that might be making the staining worse is a chlorinated dishwasher detergent or a lot of chlorine in your water since chlorine in solution with water releases oxygen making more oxygen available for bonding with the iron in your knife blades. It's like if you have iron in your water or rust in your washer and when you use chlorine bleach you get little rust spots on the white clothes. Then you have to treat them with Qwink or a similar acid product to remove the rust stain.
 
Thanks Tom and Lighted, I do use Mayo and never rinse that off, I will now. Our water does have a lot of chlorine in it also. Is there a DW detergent that would we the best to use with my high clorine condition? I will clean the knives with my stainless steel cleaner and see if that takes off the rest of the marks. Luckily we do not get rust marks on the white laundry.

Mike
 
Tom,

What protects stainless steel from corrosion is that the high chromium content results in a very thin layer of chromium oxide to form over the metal. It's microscopic and invisible, but it prevents oxygen from attacking the iron in the alloy and therefore is is resistant to rusting.

Chlorine atoms, in sufficient concentration, heat, or time, will attack the chromium oxide layer and during the time that it is missing the iron atoms are vulnerable to rusting.

This is the reason why mfg's of stainless cookware suggest that one refrain from adding salt to a pot of water (such as for pasta) until the water is boiling. This dissolves the salt readily and prevents high salt concentrations from forming around grains at the bottom of the pot, which could cause pitting if allowed to form. Pitting is especially bad because it tends to feed on itself. So a highly polished stainless steel surface doesn't only look good, it also helps it resist corrosion.

Various acids are used to clean stainless steel and encourgage the reformation of the thin chromium oxide layer. This is called "passivation". One commercial product uses citric acid - and I've found that a cut lime will remove the rust/stains from knives quite well.
 
Here too.

That happens here too. we have a KA, and it is the knives and usually right where the handle joins the "blade". I always wondered if it is because the KA dumps the dw powder regardless of brand right down on the silver ware, Then again maybe it is the mayo or mustard and some kind of chemical reaction as Mark stated.
 
Get some stainless-steel cleaner (Cameo, as suggested before, for example, although some people also recommend Bar Keeper's Friend) and, using a sponge, clean the flatware, rinse well, then run them thru the dishwasher. In my experience, there are a couple of things that cause that: one, it can be that the flatware is not made from the better stainless steel, those tend to react with mustard, mayo, lemons etc; two, even if you have excellent stainless steel, they *will* rust if you clean them with SOS and/or Brillo pads. As a matter of fact, you'd be better off washing all your pots and pans in the dishwasher and laying off the steel wool pads altogether -- if things don't come off the dishwasher clean enough, either run them thru another cycle, or clean them using Cameo. If you must wash them by hand with a cleaning pad, choose something that can't rust, like a stainless steel or brass wool pad, for example, or one of those 3M sponges that have a more aggressive side. I think the SOS pads are leaving small amounts of iron on your flatware that then rust in place.
 
Cameo and 3M Pads

I agree with earthling177 that Cameo and 3M pads are very useful in taking care of stainless. On my Farberware cookware, I use the blue 3M pads (made to be less aggressive than the green, hence no scratching). Cameo and a sponge work very well on flatware.

If something made of stainless has wood or Bakelite handles, it does not belong in the dishwasher, though. The heat and chemicals will dry out wood and loosen the epoxy adhesive usually used to fasten the wood to the stainless. With Bakelite, the problem is that dishwasher detergents (with chlorine or enzymes) attack the material. Bakelite is made by combining phenolic resin with wood flour. Since the wood flour is an organic material, it gets attacked by the detergent exactly as if it was food.

Most Bakelite damage can be attended to by polishing the plastic with Meguiar's or Novus plastic polish, or with Brasso. This will polish the damaged top layer away, exposing undamaged Bakelite underneath.

I'd also like to recommend that cookware in general NOT go in the dishwasher, if you want really good performance out of it. The dishwasher doesn't live that can remove every last trace of cooking film or starch film from pots and pans. They may be clean enough for most people, but they will have a layer of cooking film that will make them prone to sticking and scorching. I have always hand-washed my cookware, and I can count on it not to cause problems. It looks like new, and therefore it cooks like new.
 
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