oxalic acid, what is it?

[Frankthetank]

I keep fearing about this stuff but am not 100% sure what it is. Were can one get some, and could it be used on a bike that I'm trying to preserve the original paint on, I only want to remove the surface rust?

Thanks.

 

[danthrift71]

Oxalic Acid (OA) is the wonderstuff in the OS BMX community for removing rust without harming chrome plating. I've never used it but seen chrome parts and bikes brought back from the grave. I've never heard of anyone using it on a painted surface so I can't comment there. I've had some success removing rust with a vinegar bath on my chrome parts. You may want to find something thats rusty and painted that you don't care about and test that first. I've seen some dead paint brought back around with a good, gentle wash and wax. Good luck and post pics of your progress.

 

[Frankthetank]

But were can this stuff be bought? I can deffinatley try some on some chrome I have.

 

[udallcustombikes]

It is sold as Wood Bleach. I have heard that you can get it at hardware stores, ACE, Home Depot, Lowes. I have never looked for it myself so I can't say for sure where in the store it would be.

 

[Frankthetank]

Thanks fellas. How bout the vinegar bath, how's that work & how do you do that?

 

[thom]

Maybe you will have better luck finding it on the left coast. I tried for quite some time to find it here in western NC and never did. Most hardware & home store employees never heard of it and the wood bleach they offer says nothing on the package about oxalic acid.I was beginning to believe it's an April fools joke someone started.

 

[chimichanga]

check your local woodworking store. I get mine here...
http://www.rockler.com/product.cfm?page=19462

 

[Rustinkerer]

Maybe you will have better luck finding it on the left coast. I tried for quite some time to find it here in western NC and never did. Most hardware & home store employees never heard of it and the wood bleach they offer says nothing on the package about oxalic acid.I was beginning to believe it's an April fools joke someone started.

I picked up a pound on ebay, under chemicals. They use in in photography too, I think. It's also the main ingredient in Bar Keeper's Friend, which you should be able to get anywhere.. -Adam

 

[danthrift71]

The vinegar bath is simple. Place part in vinegar. Let sit for a while. Vinegar will not harm metals. I have seen it remove the zinc (I think it is zinc, galvanizing) from washing machine hoses, So I am a firm believer in testing first. I personally have used it on chrome plated Schwinn parts with good result.

This is just an idea. Others may chime in with their experience. Once the rust is removed, one of those "Clay Bar" kits from an auto parts store may be the ticket to remove the oxidized layer of "dead" paint and brighten the original finish.

 

[scrumblero]

 

[crump582]

I have seen it at Lowes here... the can actually said Oxalic Acid

 

[Buster1]

Look at my thread in the build area for my '59 Jaguar, used and documented oxalic quite a bit. Great stuff, but be careful with it and wear protection.

Bought mine in a similar tub from Sherwin Williams. $5 or so.

I however didn't have as good of luck with vinegar, but that was on corrosion on aluminum.

Good luck.

 

[big john]

I have used OA on several different bikes. I usually bath my rusted parts for 18-24 hours. Painted surfaces, stickers, none of these are affected. When removing the part from the bath there is a yellowish/white "film" all over it. I wipe it down to see if I need more bath time or if the time it was in was sufficient enough. If done, wash the part again generously with water. Then wash it with a soapy water. I then coat it with WD40 (inside and out), whatever surfaces are exposed to the bath. I wax the parts after all of this. Here is a bike that was given to me because of the "unrestorable" condition.

john

 

[Frankthetank]

Thanks all, really good info here. One more question, how do you guys get rid of it once you done using it, just dump in the grass?

 

[Buster1]

Sink or gutter with a lot of water. It's a fairly weak acid and extra water helps neutralize it.

 

[Danimal]

I want to add that a SAFE alternative to OA is CAP (citric acid powder). It is food preservative and sold in the Kosher section of grocery stores. Problem is, it only comes in small quantitys. You can buy it in bulk on eBay for short money. I mix 1 cup of CAP to 1 gallon of water and fill a big plastic bin. Let rusty chrome sit for 24 hours or so and rust will brush off.

As I said, it is 100% safe! No toxic fumes, and you don't even have to wear gloves. You can keep it and reuse it for a long time then just dump it out. OA use needs much more caution...that's all I'm saying.

 

[rico]

Wow !, Great INFO. :wink:

 

[Danimal]

Btw, a GREAT demo of CAP is here:

http://bmxsociety.com/topic/38436-citric-acid-powder-cap-rust-removal-demo/

 

[thom]

I predict that CAP is like oxalic acid in that no one within 150 miles of here has any or has ever heard of it. I'll check tomorrow. :wink:

 

[abe lugo]

I looked into CAP, it works the same but a different type of acid so the time to affect the rust is a bit different. If you order it on ebay you get the best price per pound.