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Electrolytic Cleaning or Hot-Tanking Help Needed

2003

I would like to build a electrolytic cleaning tank to clean rust, paint, etc off of an old gas tank from a tractor I am rebuilding.
Can anyone provide me with information on the formulary I could use and procedure?
A friend of mine told me about an article he read, that used a heavy plastic tub, soda, and a battery charger [on eBay or Amazon] to supply DC voltage.

It seems to me that something is missing here. Any ideas on this?
Also, would there be any way to make a hot-tank or hot dip?

What type of tank would I use that wouldn't interfere with the cleaning process?

Thanks for your help to those that reply.

Jerry Abbott-
Laurali Arabians - Brush Prairie , Washington, USA

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Jerry, there is enough to electrolytic cleaning (and it doesn't remove rust anyway) that I think it just isn't practical to do this. Can't you find a service (a plating shop or paint stripping shop) that already has the tank, the rectifier, the cleaning solution, the pickle tank, the phosphatizing system, the rinse tanks, the waste water treatment system, etc.? You could probably have your gas tank stripped, cleaned, pickled, and phosphatized for less money than you will spend just building a jury-rigged electrolytic cleaning station that will be unsafe, will leave you with an environmental mess, and won't properly protect the metal anyway.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003

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There are types of cleaning that WILL clean the rust out of a gas tank. Please refer to the following page for an inexpensive, effective, way to accomplish the cleaning of the inside of a gas tank.
http://users.eastlink.ca/~pspencer/nsaeta/electrolysis.html

David Bickford
- NY
2003

The page you referred Mr. Abbott to is a pretty good one, and we're happy to reference it, Mr. Bickford.

No one is denying the validity of electrolysis--virtually every plating installation includes an electrolytic cleaning tank. I probably fired up a hundred before you were born.

But it appeared to me that Mr. Abbott wanted to strip, de-rust, and finish the outside of his gas tank because he mentioned removing paint, and getting the rust "off", not "out". And if he wants to clean the inside, what would he need another tank for anyway?

There is nothing incorrect or misleading in my posting. Electrolytic cleaning may remove loose rust 'dust' in the same sense that a scrub brush does, and this may well be enough for the inside of a tank, which is protected from the elements and filled with non corrosive petroleum products. But an acid pickle of one type or another is required to dissolve rust in preparation for re-painting the outside of his tank. And a proper OEM-style paint prep also involves phosphatizing, as mentioned. A shortcut might involve de-rusting and pseudo-phosphatizing with a phosphoric acid product.

The page you referenced also talks about restoration of artifacts, which is a fascinating subject and which involves electrolytic treatment, but it is really quite different from what we are discussing and doesn't work the way the author of that paper thinks. Rather, electric current is applied in an appropriate electrolyte to try to actually reverse the corrosion process, like running a movie backwards. You don't want to blow the rust off the parts with scrubbing bubbles in this case, you want it to hang on where it is and be converted back to metal.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003