Restoration Tip: Electrolysis Derusting

[maple_leaf_eh]

Originally Posted by Bob Carriere

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Washing soda is readily available in rural Home hardware stores.

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I used a mild lye solution.....also from Home hardware..... but it is caustic and the drum can only be dumped on a heavy rainy downpour.

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if you use a cast iron plate it will color the part being cleaned jet black......

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What brand is the washing soda? Arm & Hammer is "So Clean, Super Washing Soda", and supposedly Walmart, Zellars and Canadian Tire sell it. Pfft! None on the shelf or in their on line catalogues. I was planning on visiting Home Hardware and Tractor Supply Company next.

So you make a solution of lye and washing soda? Sounds like a chemistry hazard in-waiting.

The colour is a good tip. The plates I have are ordinary carbon steel. Colour is not so much an issue because the parts will all get painted over. But removing the old finish and surface rust is secondary to getting the rusted swivels unseized. I will try lying them in a shallow pan with holes for solution circulation. Saddly, most of them are crusty with wood fibre or pits. The hardware is important to the project because some are odd little short and coarse thread woodscrews. [I'm stripping circa 1946 C No.7 .22LR rifle chest hardware from derelict chests for resale on the collector's and No.15 sniper rifle chest reproduction market. Special deal for any MLU'ers who want a set.]

I am going to politely decline using stainless steel. A few of the forums I read talk about hexavalent chromium compounds released by reverse electrolysis of stainless (anyone remember Erin Brockovich?).