rustbucket49
Well-known member
This is my first thread on TGJ, but have posted several times on Jalopy Journal and RRJ. I have started a new thread here on an existing subject because I know a lot of times people never read posts between the first and last ones.....
I was reading through the thread about Rust Removal by Electrolysis and several discussions were made referencing the use of stainless steel for the sacrificial anode. The question came up about the generation of chromium. Although I can't provide a chemical balance equation for the process or the ultimate correct answer, I can search the web for opinions from those smarter than I.....
I found (as most of you probably have as well) NUMEROUS references stating NOT to use stainless for the anode due to the chromium issue. I also found the one below that gives a slightly different spin on it: Read on....
Problems with Stainless Steel Anodes
"...Some thoughtful correspondents have pointed out that the use of stainless steel for the positive electrode (anode) may have some undesirable consequences. Most stainless steels contain high percentages of chromium and nickel which may be released into the bath as the anode is slowly eaten away. These are likely to be released initially as soluble cations just as the iron is released initially as ferrous ions. However, since all three cations are being released into an alkaline solution, they are likely to be immediately converted to insoluble hydroxides or oxides and form encrustations on the electrode or fall to the bottom as sediments. In this bound form the nickel and chromium are likely to be less hazardous but nevertheless waterproof gloves should always be worn when working with the bath and the bath sludge should be disposed of appropriately. It may be better to avoid the problem entirely by using simple iron electrodes and brushing the sludge off regularly......"
Even with this different spin, this source - like all the rest - recommends NOT to use a stainless steel anode. So there is still a little confusion that probably needs to be clarified by a qualified chemist - which leads me to inject an analogy to possibly give you some more food for thought.....
Let's say you just brought your newborn baby girl home (OR your son-in-law just brought home your brand new granddaughter). You will do anything to care for her, keep her safe and healthy. Your buddy is over at your house while you happen to be mixing her formula using tap water. He says, "Dude, I'm not absolutely sure, but I think that water has deadly chromium in it"... Would you use it???? Didn't think so....
My point being that if you have information that suggests something you're doing could be hazardous or unsafe, why keep doing it. Can you not afford a couple of pieces of rebar or a trip to the junk yard to pick up some scrap iron to clean that "valuable" crescent wrench or pulley?? If not, you sure won't understand hydrogen embrittlement either.....
...my $0.02 worth - FWIW, I don't use stainless......
I was reading through the thread about Rust Removal by Electrolysis and several discussions were made referencing the use of stainless steel for the sacrificial anode. The question came up about the generation of chromium. Although I can't provide a chemical balance equation for the process or the ultimate correct answer, I can search the web for opinions from those smarter than I.....
I found (as most of you probably have as well) NUMEROUS references stating NOT to use stainless for the anode due to the chromium issue. I also found the one below that gives a slightly different spin on it: Read on....
Problems with Stainless Steel Anodes
"...Some thoughtful correspondents have pointed out that the use of stainless steel for the positive electrode (anode) may have some undesirable consequences. Most stainless steels contain high percentages of chromium and nickel which may be released into the bath as the anode is slowly eaten away. These are likely to be released initially as soluble cations just as the iron is released initially as ferrous ions. However, since all three cations are being released into an alkaline solution, they are likely to be immediately converted to insoluble hydroxides or oxides and form encrustations on the electrode or fall to the bottom as sediments. In this bound form the nickel and chromium are likely to be less hazardous but nevertheless waterproof gloves should always be worn when working with the bath and the bath sludge should be disposed of appropriately. It may be better to avoid the problem entirely by using simple iron electrodes and brushing the sludge off regularly......"
Even with this different spin, this source - like all the rest - recommends NOT to use a stainless steel anode. So there is still a little confusion that probably needs to be clarified by a qualified chemist - which leads me to inject an analogy to possibly give you some more food for thought.....
Let's say you just brought your newborn baby girl home (OR your son-in-law just brought home your brand new granddaughter). You will do anything to care for her, keep her safe and healthy. Your buddy is over at your house while you happen to be mixing her formula using tap water. He says, "Dude, I'm not absolutely sure, but I think that water has deadly chromium in it"... Would you use it???? Didn't think so....
My point being that if you have information that suggests something you're doing could be hazardous or unsafe, why keep doing it. Can you not afford a couple of pieces of rebar or a trip to the junk yard to pick up some scrap iron to clean that "valuable" crescent wrench or pulley?? If not, you sure won't understand hydrogen embrittlement either.....
...my $0.02 worth - FWIW, I don't use stainless......