Rust Removal - Oxalic Acid

I ran across "Oxalic Acid Rust Removal" this morning while researching some stuff online. I did a search on the forum and didn't come up with any threads discussing this method l so I decided to start one. Looks like it could be a really good method for removing rust on bars, chains, fasteners, and all kinds of other parts. Apparently the stuff does not attack paint or the base metal. It also does not affect chrome. I have read about the electrolysis method using washing soda, a battery charger, and sacrificial anodes, which seems to be a lot of time and work. This method appears to be much easier and has quicker results.


Found some pretty impressive before/after shots on a couple different sites.

The only thing used on the clamp, other than the oxalic acid solution, is a white scotchbrite pad to clean the part after. I guess that one is not abrasive enough to scratch the chrome.

This one is a bicycle clamp.




A cylinder head. (Obviously)




I'll have to do some more research on the solution concentration. From what I can gather the effective concentration level is low enough that no extreme safety measures would be required (such as respirator, aprons, etc.). Just basic hand and eye protection. The stuff will apparently irritate skin if not rinsed off after contact and it goes without saying that you don't want to drink/eat the stuff. I read (have not verified yet) that it can be safely and legally disposed of down the drain if diluted properly.


Here are links to Google searches where I found the info. The first result in each is the one you want.

Google Search - Bike Clamp

Google Search - Cylinder Head


I think this stuff would work great for de-rusting old bars, especially ones with painted logos that you don't want to disturb. Will definitely be trying it out on some chains as well as I have some old 1/2" and 7/16" chains that are pretty rusty but have a lot of cutter life left. I just ordered 5 lbs of the crystals off of "Evilbay" and will be trying this stuff out soon. It was only $20 with free shipping. Way too cheap for me to pass up trying this stuff out.

Please Feel free to add/discuss in the meantime.:msp_thumbup:

I'm interested how this stuff will work on rusty bars. I just picked up an old 16" pioneer roller nose bar that is pretty rusty. I was also looking into electrolysis to take the rust off.

I just picked up an old roller nose too. It's pretty rusty. I'm going to try vinegar. I'll post pics when I get a roundtoit

Wow,that worked great. How do you get rid of the left over waste?

AKDriveSprocket said:

Wow,that worked great. How do you get rid of the left over waste?

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Those were done by two different people on other forums. I just linked to the pictures to show some before and after using this method. I haven't tried it myself yet.

I'll post pics when I try it out myself.

Bryon - I've tried a lot of things, but this has some promise. The questions that come to mind the fastest:

(1) - After applying the solution, how long does it take to reach the desired results?
(2) - Can this stuff be stored? (like in a 5 gallon bucket)

Subscribed ... opcorn:

EDIT: Did some digging. Found that the answer to #1 depends on how strong you mix it and how heavy the rust is. Does not appear to cause any 'damage' if you leave it immersed 'too long.' The solution can be stored safely and used over and over. Some have stored in large containers and done entire bike frames. No mention anywhere of how/if it will affect paint.

This was a 'rust thread' with some good info (and a few comments):

http://www.arboristsite.com/chainsaw/110719.htm

Philbert

Warped5 said:

Bryon - I've tried a lot of things, but this has some promise. The questions that come to mind the fastest:

(1) - After applying the solution, how long does it take to reach the desired results?
(2) - Can this stuff be stored? (like in a 5 gallon bucket)

Subscribed ... opcorn:

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Pretty neat stuff. It will also pull rust stains out of cloth. I came across it and have used it to pull the oil out of wooden gun stocks before refinishing.

muratic acid,,removes rust really fast. available at any lowes,home despot, or meeeeeenards

Citric acid works real well. You can get it from any wine making store. Non toxic (its vitamin C) and doesn't seem to do anything to your skin. My dad uses it to remove rust from old hand planes without damaging the japaning coating. (a sort of baked on tar paint stuff) Same stuff as evaporust, and far cheaper.

i've used "wood bleach" (oxalic acid) for many years, it can be found in most hardware stores, i mainly used it to soak old beer cans that needed it for my can collection, won't hurt the paint unless left in too long, pretty amazing what it will do, i buy the powder type, it works best when mixed with hot water...........................

I believe the kitchen cleaner "bar keepers friend" is 5-10% oxalic acid by weight.

Deprime said:

I just ordered 5 lbs of the crystals and will be trying this stuff out soon.

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Well, how did it work?

Looks like it works great. Thanks for the tip de N4SJ

opcorn:

kr5258 said:

Well, how did it work?

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I got the stuff in but have been busy with storm cleanup around the house and a few other necessary projects. I will definitely get some before and after pics when I try it out. Hopefully some time in the next week.

subscribing

IEL said:

Citric acid works real well. You can get it from any wine making store. Non toxic (its vitamin C) and doesn't seem to do anything to your skin. My dad uses it to remove rust from old hand planes without damaging the japaning coating. (a sort of baked on tar paint stuff) Same stuff as evaporust, and far cheaper.

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As a point of clarification, both citric acid and ascorbic acids are weak organic acids but vitamin C is a form of ascorbic acid. Both citric and ascorbic acids are found together in citrus fruits but citric acid has one more oxygen atom than ascorbic acid (citric acid formula is C6H8O7).

pretty interesting info.
opcorn:

mcginkleschmidt said:

As a point of clarification, both citric acid and ascorbic acids are weak organic acids but vitamin C is a form of ascorbic acid. Both citric and ascorbic acids are found together in citrus fruits but citric acid has one more oxygen atom than ascorbic acid (citric acid formula is C6H8O7).

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Learn something every day. Maybe we learn that in grade 11 chemisty? Find out in a few months...
Either way, citric works well and is very safe.

I have also heard of molasses removing rust? I might spare a little of my oatmeal topping to test it on a rusty pickaxe.