It was already cracked (the rust covered up etch) and your an idiot.

Good to know, i'll keep this in mind. i've got an old keller power hacksaw that has... a "small" amount... of rust that needs removing.

Just bought some evapo about to see if it really works.

Thanks for an excellent cautionary and educational video. Will fully submerge the item, got it.

Exactly, Evaporust leaves an etched line if the part is not fully submerged. I learned this about the second time I ever used it!

I prefer citric acid for most jobs. But if I need extremely fast results I use muriatic. But both of these will eat up the base metal as well if left in too long.

I put a bunch of old icky hand tools and rusty machinery tools in a 5 gallon pail with evapo rust. I put a lid on it so i literally forgot about it. about 6 months later i realized oops. I opened the pail and everything was black. Winter was coming so i just left them in there and the following spiring everything was a light grey color and looking brand new.

Here’s the rescue video. The etched lines were between 5 and 10 thou deep, and all came out with a light skim. kzfaq.info/get/bejne/a9OXl86K1b3Sn58.htmlsi=aumGbeXlEaNbbaEJ

I've been meaning to buy some for a couple of large knives I have (my father let them get rusty, then I got them after he died). Now I know how important having the metal fully submerged is.

Nice save - definitely better than living with it.

Thanks for posting this information. I wonder why no one talks about Rust 911, which comes in a concentrated form and can be diluted up to 16:1. I have a gallon but have not had the time to try it out to see if I am satisfied with its performance. They do recommend a certain start point but if it works, it is cheaper than Evapo-Rust.

80 year old mine mech. Chased lots of cracks over the years. This sounds ridiculous to me. The crack was there I'm sure or is a bad casting flaw perhaps. You need to use crack checker, following directions. You will be surprised what you will discover in many critical parts

😂😂 loser it was cracked prior to going in the evapor rust you just uncovered it.

👀good work Mark 👍👍.

Sorry to hear you ran into that problem. That kind of thing is why I bought 4 gallons of it when i was redoing one of my drill presses....you can also if you dont have enough volume, put it in a garbage bag and use that to reduce the volume you need. You may also have had better luck for the part that was out of the liquid to put paper towels over it to get the entire surface moist...then put a lid on the container to reduce evaporation/keep the fresh oxygen cycling past to a minimum. I also check my parts after 2-3 hrs...I have never had to leave anything in for half a day even for extreme rust. So you may have left it in too long as well. In any case thanks for sharing, as it is a good thing to keep in mind when people use stuff like evaporust.

put the object in a plastic bag , ad some evaporust and position the bag so that the object is covered by the evaporust everywhere. problem solved.

I don't get it. The diagonal line looks like Weld Seam or where two ends are forged together. It looks like it etched a bit deep. I'm just saying that's what it "looks like". I'm not saying that's what it is. Alternately, it looks like a defect. It cracked while in use or maybe like thermal shock or something. It' looks too "Neat" to be the result of acid etching ? Again.. To Me.

The amount of negativity and know-it-allism in the comments is astounding as always. This is a great tip and I appreciate it! The interaction with the air at the surface of the liquid must cause a very fast oxidizing process. You could add just a little weld to those spots and sand them flat. TIG would be ideal.

I've been using evaporust since I saw a few machinists and tool restorers use it. Does it have a shelf life? Because the first few times I used it (poured it in a tray, then into a glass jar) it worked great. I poured some fresh from the jug into a larger container for larger parts, and it didn't seem as effective. Like, every time I checked it, the rust was still there.

Thinking about it, it kind of makes sense - right at the boundary between air and liquid, you've got a ready supply of oxygen corroding the surface and a chemical agent actively removing the corrosion. Normally with surface rust, it stops at the surface because the rust keeps the oxygen away (hence protective oxide layers). When you react it away like this though, oxygen once more has access to form new rust.

Those lines don't intersect as the flywheel was in a liquid, I've never seen Evapo-Rust remove that amount of material off any metal I soaked in it. Also the line across the face isn't straight as it should be if it was a water line, I think @hughezzell10000 might be correct about a crack or a flaw in the material were the Evapo-Rust may have highlighted the Flaw. Just like Mana fluxing does.

This seems suspect. I've left rusted parts, including cast in evaporust for months at a time and never had anything like this happen. Always great results. In fact, I tried the same test with about a dozen different products and the only one that did any damage was an older rustoleum product that doesn't seem to be available now.

any one who uses the stuff enough eventually has this happen to them

If you do not fully submerge in the fluid, the top layer interacts with the air. Follow the directions.

I had this exact same thing happen when I left a metal rod standing up in a glass of vinegar that I used to remove rust from things for a few months, it removed the metal and etched it a bit where it was fully submerged but it REALLY etched the metal right at the surface to the point it was half as thick there. I think it may have to do with oxygen being available right next to where the acid is actively removing oxidation

Magniflux it. I thunkbit is cracked long ago.

I just wanted to say, that not only is it cracked. You have carbon inclusion in the flywheel

Alright, so to add to the question about the part being half-out, it was resting at that angle, and the oxygen + Evapo-Rust = microscopic etching circuit? And submerging the part completely would prevent this? And additionally, if I had a metal plate that I wanted to play with, I could leave small pools of Evapo-Rust on it and the interface between the pools and oxygen would create neat patterns?

Was the part cleaned with a cleaning solvent or solution prior to evaporust exposure?

I find I'm questioning your hypothesis.The lines dont join up on the 2 surfaces, did you have it on that angle in the partial soak? BTW, the only thing the TDS mentions that is remotely relevant is full immersion. Seems more likely it exposed those defects. I'm not being harsh, but I expect neither was Evaporust.

Instead of Evapo - rust exposing a crack in your flywheel you should be out trying to save your country. Now hurry up and remove my comment.

That is not from evaporust.....thats from the chemical being used on a part with problems is more likely.

So the actual warning should be…. Make sure to follow directions, and have enough liquid to cover the part.

Yeah, bloke, the Evapo-Rust didn't crack your flywheel. It merely exposed a crack on your flywheel that was co:ered in rust.

1 litre of water,100 grams citric acid and 63 grams baking soda or 40grams washing soda or 30 grams Sodium Hydroxide(Caustic soda)and some dish soap

I can confirm the waterline issue. Even worse was an incident where I had hand planes on a shelf under my workbench that were in Lee Valley plane “socks”. I had a container of Evaporust that unbeknownst to me had a leak in it. I came back a day or so later and find that the soles of my planes were etched quite deeply with the knit pattern of the sock where the Evaporust leaked onto it. I decided that I had discovered a DIY way of making a corrugated plane sole.

I always put several layers of paper towel on the exposed part soaked in Evapo-rust. Don't have any problems

Had the same problem on a #7 plane. Does anyone know if this happens with steel as well, or just cast iron?

Yeah sorry to blowup your theories, but your flywheel is cracked. Had nothing to do with a liquid rust remover. The rust remover simply exposed the crack so it was visible.

oh no.....that is some serious corrosion, I watched Joe Pie's video when it came out, thank you for your information.....Paul in Florida, USA

I've never used Evapo-Rust and have no idea what the _chemical_ make up of it is but to make a mark as bad as that it has to be fairly nasty yet anyone I have watched restoring rusty parts has not used gloves when immersing their hands in the liquid. I am *not* doubting your claim, just curious as to how the flywheel was mutilated like that. I have some rusty bits that need cleaning up and understandably I don't want to suffer the same fate. I hope you can work the damage out of the restoration. *Thank you* for the heads-up about this and for the video. 👍

Read the warning label on the Evaporust; "WARNING! Do not use on metal objects"

The exact same thing happened to me. I no longer use Evapo-Rust.

If this is truly the result of being half submerged, wouldn't the opposite side of the flywheel have the same etch pattern? I don't doubt your observation, But I would expect this damage in at least 2 places, not just all the way around one area.

good hint thanks

The evapo-rust solution and oxygen reaction.

I had this happen to a car flywheel using the Bilt Hamber equivalent. Same story, half submerged. Had to get it skimmed.

Right as it started looked like a soak line to me, bummer that got you on that part. On the visible face as well I assume?

That's nasty. I knew you weren't supposed to leave stuff half out of the solution, but i thought it would just leave a stain, not etch a groove. Given the right belt, you could definitely sand it out. The 3M 36 grit belt i use for removing scale and draft angle from castings would sand the run right off the when. 👹

Could it be porosity?