CLR again.

[Frosty]

Just recently Charlotte brought up CLR as doing a good job of derusting iron and steel.

Well today I needed a pickle for copper and PH down is too slow. Muriatic did a good job of removing the fire scale but caused the copper to tarnish as soon as it dried. for reasons I'm sure folk who work with copper alloys have known for centuries.

Anyway, Deb suggested trying the CLR under the sink and it worked a treat. Nice clean copper and no tarnishing.

Frosty

Edited August 25, 2009 by Frosty

[Charlotte]

Glad to hear it that it works on copper oxides. I suggested in the origonal post that CLR is good where finish is important. Lactic acid with the surfactants makes good cleaner but no where near as strong as HCl (muriatic) acid. Don't expect it to etch you Damascas or reveal you Hamon. ;)

[Sask Mark]

I believe CLR is phosporic acid with some detergents added, isn't it? It sure smells like the phos acids I used in labs.

[Charlotte]

I believe CLR is phosporic acid with some detergents added, isn't it? It sure smells like the phos acids I used in labs.

Yes it smell bad, but it is Lactic acid and surfactants per the MSDS.

I had assumed that it was a mineral acid myself until I looked up the MSDS.

I made the origonal posting (http://www.iforgeiron.com/forum/f21/maybe-better-way-remove-rust-14105/) after I checked it out and looked it up.

Long story short. After my father died my mother kept the shop as he left it.
That included one gallon plastic jugs of muriatic acid sitting in the middle of the floor. Over time the Hydrocloric Acid vapor passes through the plastic and put rust on every piece of exposed steel. I've been in the process of trying to recover the steel with out damaging the steel further. Items like the squares need to be cleaned without obliterating the ruleing lines. That is where CLR really shines. Removes rust with out etching steel.

[thecelticforge]

I have also found that ketchup is an excellent copper cleaner also.

[Charlotte]

I have also found that ketchup is an excellent copper cleaner also.

There are any number of acids that will remove oxides from copper. The trick is finding a formulation that will remove the oxide without etching the copper.

The acid in ketchup is vinegar.

[Sask Mark]

Yes it smell bad, but it is Lactic acid and surfactants per the MSDS.

I had assumed that it was a mineral acid myself until I looked up the MSDS.

I made the origonal posting (http://www.iforgeiron.com/forum/f21/maybe-better-way-remove-rust-14105/) after I checked it out and looked it up.

Long story short. After my father died my mother kept the shop as he left it.
That included one gallon plastic jugs of muriatic acid sitting in the middle of the floor. Over time the Hydrocloric Acid vapor passes through the plastic and put rust on every piece of exposed steel. I've been in the process of trying to recover the steel with out damaging the steel further. Items like the squares need to be cleaned without obliterating the ruleing lines. That is where CLR really shines. Removes rust with out etching steel.

Thanks for the info Charlotte.

[Finnr]

I clean copper antiques with a rag dampened in white vinegar and salt . The vinegar provides a mild acid and the salt is a mild abrasive.

Finnr