I warn all of you to be very careful using muriatic (hydrochloric) acid. It does a great job etching metals but you need to watch its progress and be sure to completely neutralize it prior to your next step.

If you are NOT fully aware of the hazards of hydrofluoric acid, DO NOT TOUCH IT. IT is nothing but bad. Bad. Bad news.

Ospho, naval jelly, rustmort, and all the other phosphoric acid containing are the way to go. The advantage is that this acid reacts preferentially with the rust so the attack to the good metal is minimal.

I'm going with what Harry recommends, as from what I can recall from talking at a cars & coffee a long time ago, I think he has some experience as a chemical engineer..... and rattle can bus painter extrordanaire! ;)

This is what I like with the electrolysis - it doesn't touch the healthy metal. Plus it leaves no residue.

/Johan

I've used many types of rust converters including a rattle can product from Rustoleum called "Rust Reformer".

Available in WalMart.

Converts the rust plus leaves a coating of flat black paintable surface.

Very handy for certain applications. Including gardening tools - I sprayed a machete blade yesterday to help manage rust issues.

Here, here!
Muratic acid, is a great compound, but to use effectively you have to understand it completely. It is a powerful rust, plating(zinc, cad ect) remover. I use it to prepare steel for TIG welding, where oxides and plating metals will contaminate the weld zone. Used properly, it works well, used sloppily is incredibly dangerous, splashing and fuming are just a few hazards. Drop the wrong material into the mix and you will be rewarded with a hazmat mess, with the resultant trip to the ER. I only open the jug when a charged hose full of tap water is close by my hand and with full face protection. When you get this stuff on your skin, you will know immediately.

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