Evapo Rust information

[Real1]

Uhhh... No.

I am not knocking either of those things as rust remover but they are both acid, and Evaporust is not acid. It is PH neutral. Acid is going to attack the base metal on some level or another because it is acid. Extra care is needed.

Naval jelly and most rust removers from days gone by (and today for that matter) are based on Phosphoric Acid. This includes Naval Jelly, Ospho, Jasco, Coca Cola (LOL), and a million others. My experience with these, which are often called "rust converters", is that they never get all the rust. They get some of it and then skin over whatever is left with a black phosphate. While this can slow down rust a lot, it just ain't what I am after if I am trying to REMOVE ALL of the rust. Evaporust will get all of it, given long enough to work. Once you are down so the only rust is in deep pits, the surface area of the pits is tiny and it takes forever, but it does not stop. Phosphoric acid will skin over with black phosphate and stop.

Vinegar is Ascetic Acid. It removes rust. Being an acid, it also attacks base metal. It can work well. You probably want the canning grade. It is stronger.

Citric acid probably works too. It is also in the canning aisle, and it is also acid. I don't have much experience with this one. I have a bunch of the powder I bought trying to go after lime deposits. I hear it removes rust too. Your mileage may vary.

Muratic Acid (pool acid) is aggressive as hell and removes all the rust. It also attacks the good metal pretty aggressively, though slower than it attacks the rust. Read up on this one and how to handle it so you don't have any explosions. Protect your eyes and everything else. DON'T breathe the fumes. It ruins almost anything it touches. Don't keep it in your house or shop. It can be sitting in a sealed jug, and other iron and steel stuff in the same building will start rusting faster within a large radius. I can't explain that. It can be extremely useful in some situations. Your mileage may vary.

Oxalic acid is a terrific rust remover. It is an acid, so no doubt also attacks the base metal. Like all acids, it needs a close watch on progress. The best results I have ever seen on bicycles with the least apparent paint loss I have ever seen have been in CABE threads by other people. I have only used it on small parts. I like it.

So much for acids. If you want to go down a DEEP Internet rabbit hole, there are people who think they have identified the chemical in Evaporust, using spectroscopy and reading old scientific papers and so on. It is nothing you could just go out and buy in the canning aisle, I'm sure of that. If identified correctly, it is also nothing you have ever heard of unless you are a chemist. Is it overpriced? Maybe. Probably. Are there cheaper products that might have the same chemical? Probably. Are there more concentrated versions available somehow so you aren't shipping a bunch of water? Probably. I don't know. As I said, the rabbit hole is deep. I invite you all to go look. I gave up.

Evaporust in no way resembles any of those previous acid-based rust cures. I can only assume the people saying so have never actually seen any, or got any on their hands. The only old fashioned rust cure that seems similar is molasses. I understand that it works well, and is probably a lot cheaper down at the farm store. Of course molasses stinks (not that Evaporust is entirely stink-free), and molasses is going to attract bugs because it is sugar. There is a persistent ant problem in my neighborhood, and the ants went for my garbage can of Evaporust for about a day and a half. Then, they decided they did not like it at all. They never came back. Molasses also might be acid on some level, but mainly works by chelating rust just like Evaporust does. It is the closest thing you are going to get for cheap in bulk, but may be impractical for some of us to use.

There is also electrolytic derusting. The results are errily similar to Evaporust, and it is way cheaper. The trouble is it sort of works well as line of sight from the steel electrodes, so it doesn't work too well on hollow parts or mechanisms that don't come apart. Evaporust does not have that limitation. Electrolytic derusting would work awesome on something like a fender where the surface is all on the outside. Read lots of HOW-TOs so you don't get the polarity of the power supply backwards due to someone's typo. That will damage your parts. It is pretty harmless when done right, just like Evaporust. In my opinion it is going to remove paint, but in my experience so would Evaporust. Either of these methods will get to the rust even if it is under paint, and then there is nothing holding the paint on anymore.

Although well written, I disagree with your assessment of Evaporust. I know it's supposed to be base-neutral and much safer than acid-based rust removers. I've used it a lot on heavily rusted items like chains. What I was explaining previously was that it has the same effect as old-school Navel Jelly. Does a half-ass job and darkens the metal. Now if I had the time to pull it out of solution and wire brush it every few hrs....it might do much better. I never said it was the same base as Navel Jelly....you're reading into that. I said it yields the same results on heavily rusted metals.

For me, however, I'll go after the rust with acids. However, I always monitor the time in acids. You CANNOT just leave your items in there. If you think there's a possibility you'll forget, don't use them.

It's no "rabbit hole" if you're attentive & careful. Only if you're careless and/or forgetful. Acids can do in minutes what Evaporust may take overnight. The choice is yours. Except with keeping paint intact....that's where Evaporust will shine over acids. That's why you bike guys love it so.

Kevin

 

[bloo]

Although well written, I disagree with your assessment of Evaporust. I know it's supposed to be base-neutral and much safer than acid-based rust removers. I've used it a lot on heavily rusted items like chains. What I was explaining previously was that it has the same effect as old-school Navel Jelly. Does a half-ass job and darkens the metal. Now if I had the time to pull it out of solution and wire brush it every few hrs....it might do much better. I never said it was the same base as Navel Jelly....you're reading into that. I said it yields the same results on heavily rusted metals.

Fair enough.. The metal darkens because the steel had carbon in it and once the rust is gone, the carbon is still laying there. I don't think that is avoidable. It does not make a phosphate skin like the Naval Jelly I remember from the 70s, which was about the best thing around back then. What I like about Evaporust is that given a chance it will go all the way to the bottom of the pits. Generally no wire brushing either because there is no Phosphate coating blocking further reaction. Unless you are impatient, that is. I am impatient and have probably tried a wire brush at some point. I'm not sure if it did any good. The loose carbon mostly washes off with soap and water. The reaction does go faster if you take parts out now and then and wash the powdery black stuff off. If you leave the parts in a long time, and I probably do because I am trying to get all the way to the bottom the pits, then yes the surface can turn black. I haven't really ever been able to get to the bottom of the pits with the old fashioned cures. Molasses might do it.

It's no "rabbit hole" if you're attentive & careful.

Oh? Then what is the chemical?

(Hint: It might be Ethylenediaminetetraacetic acid, PH adjusted to neutral.... or not....)

 

[Real1]

Fair enough.. The metal darkens because the steel had carbon in it and once the rust is gone, the carbon is still laying there. I don't think that is avoidable. It does not make a phosphate skin like the Naval Jelly I remember from the 70s, which was about the best thing around back then. What I like about Evaporust is that given a chance it will go all the way to the bottom of the pits. Generally no wire brushing either because there is no Phosphate coating blocking further reaction. Unless you are impatient, that is. I am impatient and have probably tried a wire brush at some point. I'm not sure if it did any good. The loose carbon mostly washes off with soap and water. The reacction does go faster if you take parts out now and then and wash the powdery black stuff off. If you leave the parts in a long time, and I probably do because I am trying to get all the way to the bottom the pits, then yes the surface can turn black. I haven't really ever been able to get to the bottom of the pits with the old fashioned cures. Molasses might do it.


Oh? Then what is the chemical?

(Hint: It might be Ethylenediaminetetraacetic acid, PH adjusted to neutral.... or not....)

Fair enough as well. I'll stick to acids although when paint preservation is involved, I'll use the Evaporust.

On another bike forum, there was a pretty easy way(with pics) of making a water bed for your bike frame. On top of the poly you laid in your frame and you only needed enough Evaporust to fill in the cavity that the bike made in the poly(water underneath). Pretty ingenious, but I chickened out over the decals and such that I didn't want to hunt for, as they're only repops at that. I just need to spend the time and slowly go over the frame by hand. Tiny speckles of rust show through the paint. Something you would expect from a bike hung up in a carport in Southern CA for 40 yrs.

Kevin

 

[acg_schwinn]

Fair enough as well. I'll stick to acids although when paint preservation is involved, I'll use the Evaporust.

I've been reading the debate here between you two with great interest, but I would only add that in many cases I'm using the Evapo Rust specifically because it does remove the paint. The only question is, which paint will it attack and which will it leave alone.

It's great at completely removing spray paint, and conversely it doesn't seem to disturb (at all) finishes which I guess are baked on (thinking of factory Schwinn paint here), or otherwise so perfectly sealed (which the old Huret Hammertone was not) that the solvent cannot find any way under the surface.

 

[Dra]

Harbor freight $30 a gallon menards $20 gallon. Smaller items like seat springs nuts bolts works great and I usually just leave them soaking until I’m satisfied. I reuse it on chains, wheel hubs and bearings

 

[Andrew Gorman]

LOTS of discussion on electrolytic rust removal at owwm.org you might have to register. Kiddie pools, 275 gallon liquid totes and custon 2X4 frameworks draped with plastic are common tanks. Battery chargers and laptop power supplies are the usual power sources. I've never tried it since I am short on space in a city apartment and model T garage I share with a car, which discourages starting large rusty projects.

 

[Real1]

I've been reading the debate here between you two with great interest, but I would only add that in many cases I'm using the Evapo Rust specifically because it does remove the paint. The only question is, which paint will it attack and which will it leave alone.

It's great at completely removing spray paint, and conversely it doesn't seem to disturb (at all) finishes which I guess are baked on (thinking of factory Schwinn paint here), or otherwise so perfectly sealed (which the old Huret Hammertone was not) that the solvent cannot find any way under the surface.

Exactly. My risk in Evaporust removing something it shouldn't with my Raleigh Competition GS frame is just something I didn't want to try. It would probably be fine...except maybe the decals. But like they say, the paint is only original once. It's not going to kill me to slowly give it some kind of 'by hand' attention. Sounds like from your experience, anything sprayed aftermarket may likely come off. I think most vintage bike finishes are baked on to some extent. Not exactly like modern powder coating, but heated/baked some.

It makes sense that Evaporsut would get under and lift anything just sprayed.

Kevin

 

[bloo]

In my experience Evaporust is the wrong answer if you are trying to save paint. Apparently it works out for others, but based on past experience, I am gun shy.

 

[Late To The Party]

 

[Schwinntramp]

So yes Evaporust contains acids as well along with buffering agents to neutralize the pH. According to this patent.

US3510432A - Noncorrosive rust remover - Google Patents

United States Patent #3510432A NONCORROSIVE RUST REMOVER Albert T. Squire

Quote: Water 4000 ml. Ammonium citrate 500 gm. Sodium phosphate 100 gm. Sulfuric acid (S.P.) 30 ml. Surfactant (sodium lauryl sulfate) Sodium benzoate 5 gm. (Preservative Agent ) As anti-mold.

When you introduce sodium phosphate to water, then becomes an acid. Ammonium sulfate works as a buffer to adjust the pH.

Potato Potatoe their all some form of and acid. Watching the results closely is the key. Don’t over soak in any of them. I had good ol Evaporust eat right through spokes on a Schwinn wheel in about 48 hrs. So proceed with caution. I use Fluid Film aerosol mostly now. Spray the part down let its soak 20 minutes or so. Use brass brushes or brass wool and the Fluid Film and no black carbon deposits.