It sounds like you're using a milder mixture than me and the results are the same, I'll try diluting my batch a bit. I'm sure that the temperature also plays a role in how fast it works, I don't need to worry about making a caustic popsicle.

This is just a quick idea for those treating entire frames, but has any body thought about taking PVC piping, cuting it into halfpipe shaped troughs and then joining the peices togeather in the shape of a frame?

I know that PVC elbows won't match the geometry of a frame, but you can get around that with bendable ducting, like laundry dryer ducting, some rubber gasketing (use strips of old intertubes to sandwich inbetween the layer of the ducting and PVC) and then taping it heavily with Duct tape or what have you. SHAZAAM, you have a frame shaped soaking trough.

It's just an idea, though.

The obvious problem to that that I can see is that you'd need two troughs, each a mirror image of the other, since you'd need to turn the bike over to get both sides. Or am I missing something? Also, each size frame would require its own custom trough, and maybe each individual frame, depending on its geometry.

True, as I said it was a quick idea. It just popped up into my head, and I wasn't thinking it out thoroughly.

Still, when you cut the PVC pipes in half you wind up with two troughs...

Meh, kiddie pools still win, I guess.

You're right, you WOULD get two halves when you cut the tubes in half--it's actually a cool idea, though executing it neatly would take a lot of work. If you shaped the pipes accurately where they butt together you could join them with the same pvc cement plumbers use for dwv (drain-wast-vent) piping. Might work! If you used 4 inch pipe, the bike frame might fit loosely enough in the trough that it would accept most frames of a given size (60 cm or whatever) even if the geometry isn't identical. And most of us are only going to be cleaning bikes in our own size, right? It would actually be something like making a big fat-tubed plastic frame and slicing it in half...

When is someone going to weigh in on the electrolytic method? I tacked it onto this post because I figured that people interested in OA might also be interested in electrolysis. I posted on this separately months ago, and haven't found any knowledge or interest. Hmm.
JV

Rust removal using acetic acid:

https://www.cookhaus.co.uk/vinegar/index.htm

Wow--trying the vinegar method first looks like a no-brainer. If it doesn't work, you can always bring out the toxic heavy artillery later. I'm definitely giving vinegar a try.
JV

Plain everyday vineger gets overlooked all too often for general use. The odor is unpleasant, but at a buck a gallon it's a real bargain.

I'm going to echo some of Panters007 warnings.

All ways wear eye protection. You get one set, and that's it.

It's best not to work with this stuff when you are alone.

All ways have fresh water and some method to neutralize at your disposal.

All ways work in a well ventilated area.

Wear some form of impervious gloves and if you have one, a rubber apron.

All ways remember that bad things from checmical exposure are rarely acute except for burns. Usually problems are more chronic and based on long term exposure to low levels. An accumulation over time is what gets you.

Most of us in the chemical industry know someone who has become desesitized to a certain chemical over time due to on going exposure. Being desensitized means that just getting near the chemical will result in a reaction by your body. Usually this is just a rash but can also result in constricted airways, burning eyes, and many other fun things.

The point is, you can handle chemicals for a very long time without taking the recommended precautions and never have a bad side effect, but trust me on this when I say your body keeps a running tab.

Would you take those sorts of precautions when working with dilute acetic acid--that is, regular household distilled white vinegar? It couldn't hurt, I guess, but vinegar seems to have a pretty low toxicity. For oxalic acid, though, I'm sure it's good advice.
JV

5% Acetic Acid - Vinegar - is quite safe. At worst it is a respiratory irritant. Pure acetic acid is another story - it will burn the skin badly and could easily kill someone if they drank it. If you get your vinegar in the grocery, you're good to go. If you're going to be around it frequently, you might consider wearing a respirator rated for acid-gases. This to lower the possibility of your having an asthmatic reaction around a salad-bar.

This may have been covered elsewhere, but how do you dispose of a bucket of water with a few pinches of OA in it?

Baking soda will neutralize OA

Neutralized with baking-soda, the oxalic acid become sodium oxalate. This is also poisonous. It won't corrode metal, but it will kill a pet or child who licks it up/drinks it. Pour it down a drain and wash the bucket out. Run water down drain. Finis.

I just wanted to say that yesterday I used Oxalic Acid for the first time after reading as much info on it since before x-mas and most of it from this site and I just couldn't believe the results and how easy it was,(I did a crankset,seat post and four bmx pegs and a set of schwinn toe clips) man oh man I will be using this from now on.
Anybody know how long or how many times can you reuse Oxalic Acid it is already cloudy.

Figure that the amount of rust you have dissolved is proportionate to the amount of oxalic acid that has been used. So let's say there was an 1/8th of a teaspoon of rust on part X. You have used 1/8th of a tsp. of oxalic acid. Add this amount to the solution. But it likely won't be needed for just de-rusting a small item/area.

Here's an idea for a frame-soaking container based on Quixotegut's suggestion about fabricating a frame-shaped trough out of PVC tubing. After thinking about it for a while, I adapted that concept to this:

1. Make a wooden frame maybe 3 feet by four and 6 or 8 inches deep. Level it carefully on the ground in some convenient place and pack it solidly full of damp sand, leaving a smooth and level surface.

2. Cover it with a sheet of polyethylene and center the frame to be soaked on top of the sand, and push the frame firmly into it to leave an impression.

3. Remove frame and plastic and use a tablespoon or some other convenient tool to carefully excavate 2-inch-deep trenches in the sand corresponding to configuration of the frame--angling deeper for the chainstays to compensate for their outward flare.

4. Replace plastic, press frame down into the prepared grooves, then fill the low trenched area with OA solution. The advantage of this is that you're working with 3 or 4 gallons of toxic solution as opposed to 50 or 60 gallons.

5. When frame is clean, remove it and suck up the solution for re-use or disposal with one of those bulb syringes auto parts sell for adding acid or water to car batteries. Then refill with baking soda solution to neutralize the OA residue on the frame.

I haven't tried this yet but I don't see an obvious fatal flaw. I think I'll try it when I have time to strip the Dawes Double Blue to the frame.
JV

Thanks for all of the great info in this post. I see that most people are using OA for chrome parts. Do you also use it for painted parts (frames, fenders, etc.)? Does anyone have any before and after photos of the results on a rusty frame or fender?

I have a 1959 Schwinn Panther II that I want to restore and am looking for pointers. I want to keep the original paint, but need to remove as much surface rust as I can.

Below are three photos so you can see the rust that I have. 1) Straight from the yard sale. 2) After a light water and brush wash. 3) Original paint under 1/2 tank.

Any advice is appreciated.

I looked through this thread (and others like it) and didn't see an answer, but maybe I missed it.

How do you dispose of the Oxalic acid once you're done?

As was mentioned a few times above, acetic acid (vinegar) works very well. Let components soak, wipe them down, and then soak again (for tough jobs).

^I think the real difference isn't toxicity, but the fact that with oxalic acid crystals the end user can control the acid concentration, for better or worse. A bottle of store-bought vinegar is acetic acid already diluted to consumer-safe levels (or at least I hope...I'd hate to think that all those years dyeing easter eggs in the stuff have left me with an acute case of "easter lung").

Still, it'd be interesting to hear results from people who have tried both types of acid bath.

Oxalic acid - rubber-gloves of the type worn for dish-washing. Safety-glasses. Wear old clothes and remove same afterwards.

Acetic acid - 100% - will burn the p*** out of you. As it's a liquid (which freezes into crystals at 62F - which is why it's called "glacial" acetic acid). Gloves, good safety-glasses. Rubber apron.

This is standard laboratory safety protocol. And it's there for a reason.