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I have been researching different ways to remove rust from metal and there's plenty of methods. I tried vinegar which worked ok but took several days and the rust was probably only 75% loosened up. Then I decided to build my own electrolysis tub and give that a shot. Results can be had between 2 hours and over night. Excellent results at that. My preferred method would be evapo-rust but it's quite expensive. It does not use acid and is probably the least harsh method but still produces amazing results and best of all it's reusable for years.

This is what they say about not using stainless steel. Everything I've read says not to use it as the electrode which I'm pretty sure they mean the metal you use to attract the rust off the part you're removing rust from. They don't say whether it's safe to remove rust from a stainless steel part/tool. Anybody got an answer for me?

http://1bad6t.com/rust_removal.html

Why you should not use stainless steel:

Many people using the electrolysis method for rust reduction swear by stainless steel, stating (incorrectly) that it's not consumed, stays clean and seems safe. Stainless steel is indeed consumed when used in the electrolysis process, although slowly. The main problem with using it is the hazardous waste it produces. Stainless steel contains chromium. The electrodes, and thus the chromium consumed, and you end up with poisonous chromates in your electrolyte. Dumping these on the ground or down the drain is illegal. The compounds can cause severe skin problems and ultimately, cancer. Hexavalent chromate is poisonous. These compounds are not excused from hazardous waste regulations where household wastes are. These compounds are bad enough that government regulations mandate elimination of hexavalent chromate by 2007 for corrosion protection.

I haven't found any definitive answers myself, but from reading the chemistry section at the bottom of this page:

http://www.rickswoodshopcreations.com/m ... emoval.htm

It would leave me to comment that you would be creating magnetite on the surface of the SS.

Do you have stainless steel parts that have significant amounts of rust on them that you would need to use electrolysis?

No its just a lot of stuff has stainless bolts or studs. For instance I just did a turbo exhaust housing and the studs are stainless as well as the wastegate door and shaft. Came out looking new though.

The way I understand it, you are fine to de-rust things that have stainless parts. The issue you have is when you are using SS as the sacrificial electrode, which you hopefully are not.

The part being de-rusted loses nothing except iron oxide, so you aren't creating any hazardous chemicals.

No I am using 4 pieces of 1/2"x12" rebar wired together so the item is surrounded in an 18 gallon rubbermaid tub. My next question is now that I've removed all the rust from the exhaust housing, should I spray something like rust inhibitor on it to prevent rust at least until its used or don't worry about it? Maybe some rattle can ceramic coating?

As the write-ups mention, once the part has been removed from the solution it will rust pretty quickly, so yes I would clean things up as mentioned, dry, and then paint or protect the part from further rusting.

It did too. Took it out in the morning and cleaned with brake cleaner and it was rusted when I came home from work!