Oxalic Acid?

[cowboybob998]

i used it on the inside of one of my tanks and it seem to work ok

[Montreux_Blue]

Some different types of rust removal from a bmx forum. Never tried any of them, only relaying the message.

Citric Acid Powder (CAP) Rust Removal Demonstration

Basically, I'm mixing 8 ounces of pure CAP into 1 Gallon of water then I'm going to try and de-rust/clean up some old sprockets. Here goes...
Step 1):Measure out 8 ounces of CAP
Step 2): Pour 1 Gallon of tap water into an empty plastic bin using an empty water bottle to measure
Step 3): Grab a few rusty sprockets in varying degrees of "rustification"
Step 4): Mix the CAP and Water
Step 5): Drop in the sprockets
Step 6): Note the time (3:45pm) and come back and check after around 24 hours (meaning tomorrow, as I just did this a half hour ago)

before:




after:



I found a small bottle of CAP at a local supermarket in the kosher section, labeled sour salt.




The grocery stores usually charge around 10-12 bucks per pound. That's on the high end, price wise. Home beer and wine making supply stores usually carry it and are probably cheaper.

The best prices are off Ebay. Here's an example for $4.00 a pound and the shipping is free:

And another way.

Yeah, the Aluminum Foil thing is pretty cool. I used some light Canola oil with it, but I've heard Coke or Pepsi works really well too. Probably because of the acids. As long as there is some moisture being used with the Aluminum Foil, it seems to really work well. The light oil seemed to leave a nice shine for me.

After some research about it, I found out the reason why it works:

"Aluminium has a higher reduction potential than the iron in steel, which may help transfer oxygen atoms from the iron to the aluminium. The aluminium foil is softer than steel and will not scratch it, as steel wool will, but as the aluminium oxidizes, the aluminium oxide produced becomes a fine metal polishing compound."


I found the old photos of that demonstration which took about 5 minutes. Here they are:

Also............

"Wood Brightener" or "Deck Bleach" aka oxalic acid! You can get it at the hardware store.

Or...........

CLR

before:



after:

Or............

Rust aid will work also and its at home depot in the plumbing section.

Or............

Vinegar but they say it can cloud chrome.

if you use vinegar, just be careful and check it often don't want it do end up like this

[b.walker5]

There is some stuff called CLR that works real well on rust allso, you can get it at wall mart

C.L.R. (Calcium, lime and Rust Remover) My wife uses this at home. It's not bad as a household cleaner. Takes rust and lime stains off the bath etc, and I used to take some surface rusting of the bumpers on my twin spinner. It worked okay at this but it wasnt interested in dealing to rust on the 4x4 chassis, hence the CRC product in a previous post. It did a real nice job of cleaning oil stains on the driveway (after I spilled the bottle). Stinks like s*it though.

[Bigleo]

oxalic acid

Oxalic acid is a great rust stain remover. The downside is that it releases a low level of cyanide gas while it is working on the rust. So best done outside only.
Leo