Oxalic acid rust removal - it works!

[LEEVON]

I got an itch to try some alternative rust removal techniques and have been reading here and there for the last year or so. I have a sand blaster and soda blaster but they aren't always practical and have their place. I wanted something liquid that I could just throw parts in and forget for awhile. Lots of good stuff out there, each with it's own characteristics but I settled on trying out Oxalic Acid (OA), commonly known as wood bleach. I bought 5lbs from Ebay for $20 and it came with an instruction sheet for many different uses. For rust removal, 1-2 tablespoons per gallon is recommended. At that concentration this stuff is very cost effective if you can buy it like I did. I picked out a range of rusty things in my garage, a chrome shifter, nuts and bolts, some very, very pitted old crap, a piece of sheet metal with flash rust and a 47-54 running board support which I needed to clean up. The sheet metal with flash rust was clean in less than 1 hr. The chrome shifter looks new and I thought it was a goner. The nuts, bolts, etc took a couple days to soak as did the running board support. I pulled the support out of the solution a few times and scrubbed the loose stuff off with a brush which helped quite a bit.

Please be aware this is a caustic chemical and need to be treated as such, it is highly poisonous to humans and animals, a small ingestion of pure OA will kill you and the fumes alone are harmful. In it's diluted form it's not that bad so if you can take resonable precaution then go for it!

Here's where I get blown away with the results, this running board support looked to me like it had never been painted or possibly lost all it's paint long ago. Since the Oxalic Acid only attacks the Iron Oxide or rust, after doing it's job revealed a black coat of paint that looked almost new after 60 years. See for yourself:

[67cheby]

that is crazy !!

[flashed]

It would be nice if you could do something as big as a core support or even wheels .

[John Fabris]

Yup, that sutff works great, I have yet to use it on truck parts, but I commonly use it to remove the rust from old metal beer cans and tabacco tins, and it works great, removing the rust, but not harming any of the ink/paint on the metal.

[mpauly]

Originally Posted by flashed

It would be nice if you could do something as big as a core support or even wheels .

I've never looked into the OA method, but it seems pretty cool. Kind of like using vinegar, but cheaper. Once you mix the solution, is it reusable or do you need to mix a new batch each time. Just thinking you could have a tub of it laying around and throw in small parts when you want.

For large items, you can try electrolytic rust removal. All you need is a battery charger, some wire, few pieces of sacrificial iron (I use pieces of rebar), water, baking soda and a vessel big enough to hold your item. It's non toxic, practically free and quick (few hours to overnight usually is enough).

You can do it with any size item as long as you have a vessel big enough to hold enough water to submerge it. For a core support, you could build a low, flat box out of 2x6 lumber and line it with a 4 mil plastic sheeting. Wheels would fit in a rubbermaid bin or a plastic garbage can.

Only major concerns to worry about are:
- use a non conductive vessel (plastic is best)
- make sure you hook up the leads with proper polarity
- make sure you have proper ventilation or do it outside (the process gives off a small amount of hydrogen which you wouldn't want to build up in any concentration).

Michael

[BB72CHEVKT]

How do you dispose of it when you are done?

[LEEVON]

Originally Posted by BB72CHEVKT

How do you dispose of it when you are done?

I just diluted it with water and dumped it, if you were going to put it into the sewer you could add some sodium bicarbonate or baking soda to neutralize.

Since this is not the most aggressive rust remover in my opinion really large parts would be difficult because you would need to contain it safely and then be able to scrub the part if the rust is really heavy. If you google this stuff, you will find it's popular with bicycle restorers because it is like magic on chrome. They use big tubs and dunk whole frames, it won't eat the paint or decals just the rust. I won't rub or scrub chrome ever again, this stuff is perfect for that. I think you can keep it around too, I would have but don't have a lid for that 5 gallon bucket and I just don't want to spill it or god forbid the dog drink it or kids play with it. As cheap as it is though, didn't hurt a bit to throw it out.

[dwcsr]

I saw an article about a guy using CLR on a paint job on a early 60s car. It removed the rust pantina and the paint was left as on your piece. It was pretty amazing to see it before and after.

You should have a resperator on and in a well ventialted area while working with AO. It will burn your lungs and cause permanent damage.

[LEEVON]

I plan to do that to my '50 truck that's kind of why I started experimenting. I think the CLR might be better for a body though because the OA would have to be mixed at a higher concentration than I have already and that would be more than I'm comfortable with. I tried the solution on a rusty running board with a scotch brite pad and it didn't have enough time to do anything whereas I think the CLR acts quickly.

[Jacfourteen]

Great results, I'll have to keep this in mind for cleaning small parts.

[travlinman]

leevon... u happen to have a link to the stuff u bought?

[dwcsr]

look at this towards the bottom
http://www.chevytalk.org/fusionbb/sh.../post/1712505/

[y5mgisi]

Intresting!

[LEEVON]

Yep, that stuff contains oxalic acid and it's much more expensive. Great write-up though, and there are three CLR'd impalas that I know of now.

[stich626]

nice.. looks liek I can save my wheels//steel chome rim alum center..
cool...
u have the ebay store you got from?

[Fitz]

Originally Posted by flashed

It would be nice if you could do something as big as a core support or even wheels .

The real advantage to Oxalic Acid is it DOES NOT ATTACK CHROME. Almost every other rust removal chemical will dissolve it but OA does not.

[CEE1NG_RED]

wow!! OA it is for chrome!!

[67swb72klb]

sweet

[WestButteTruck]

So would you need to actually submerge a wheel, or could you spray some on and agitate it, keep it wet for a while, then rinse? The crap they put on the roads in winter plays havoc with my wheels and stainless trim.

[flashed]

I plan to try some when I can find a large container to put wheels or even something big enough for a core support .I need to go to tractor supply and see whats available.

[DZL1]

Flashed, why dont you just make a container as big as you need it out of wood and get some plastic tarp and lay it in the box and up over the sides. That way the liquid wont leak out. Dont know if the OA will eat plastic or not but its a thought.

DZL1.

[basemodel67]

Hmmm, I prefer to just drop acid. Hey look! That tiny pink elephant is taunting me with some tribal freak dancing

[71sierragrande]

Thats amazing, thanks for the info fellas.

[67cheby]

LMAO....pink elephant

[Alex Hayley]

Here is an ebay listing for it:

http://cgi.ebay.com/5-Lbs-Oxalic-Aci...item3a48586470