Evapo-rust

[fsauter]

I searched the forums and found no mention of Evapo-rust. First, let me say that I and none of my relatives or friends have any association with Evapo-rust. It's a non-toxic, environmentally friendly, reusable, cold-soak solution that removes rust in a few hours. I have tried it on tools and it works extremely well, so I gave it a shot on a Dutch oven lid recently. First, I cleaned the DO with lye then rinsed and wiped dry. I treated the lid by soaking for a few hours in the Evapo-rust. Clean as a whistle and steely gray. See photo as I drew it out of the bath. It seasoned up beautifully. I can post more photos if anyone is interested, but I have only done this one piece.
I got the Evapo-rust first from Autozone. Don't know if they still carry it. Recently I bought a gallon from a local car restoration shop. Gallon is about $25 and will clean about 300 lbs of moderately rusted steel. The Evapo-rust web site has more information.

http://www.evapo-rust.com

Fred

[fsauter]

And here it is after the lye.

[C. Perry Rapier]

I read all about this. It looks good, sounds good. Other than what I just read, this is the first time that I have ever heard of it. Would it be practical to set up a big vat of this to submerge cast iron pieces in? I don't know. But you could keep a sealed lid on it, like one of them big plastic containers, one of them. What are some other opinions?

[livens]

Other than being a bit $$$ it does look to be a great product.

My question is how long does it last. From what I read the active ingredient bonds to the iron molecules in the rust, and also the non oxidized iron on the surface of the peice. But it is too weak to pull the iron off of iron, so it just sticks to it. So how long until all of the active ingredient has been bonded?

Fred, you mentioned 300lbs of iron. I wonder if that holds true for skillets and the like that have a relatively high surface area for their weight?

Something I do like about evapo-rust compared to a electrolysis tank is not having that dark-grey/black iron residue to scrub off afterwards.

Im a bit of a scrooge, so for me $20 or so for evapo-rust vs. a couple dollars worth of sodium carbonate that keeps working for years... and removes carbon at the same time. I would say it could be a hard sell for those who already have a electro-tank setup. But if you dont have a tank and only have a few peices to do it might be the best option.

[Anthony Richerson]

Does it have to be neutralized after cleaning? If it eats rust I would think it would eventualy eat the iron?

[Jeff Johnson]

Does it have to be neutralized after cleaning? If it eats rust I would think it would eventualy eat the iron?

I just used Evapo-Rust ("ER") for the first time this weekend to salvage my wife's best friend's dutch oven.  She had her mom's Favorite Piqua Ware #7, and it had been neglected for years & years.  You could see the round machining marks in the bottom & walls of the DO, except where something had dribbled & pitted the surface.  A very nice chunk of cast iron, I might say (WARNING: as a newbie, many chunks of cast iron would qualify as "nice" to me!).  Disclaimers aside, it was neat to see the craftsmanship that went into making a nice smooth, wonderful chunk of cast iron versus the standard (Lodge) "melt the iron, dump it into a rough sand mold, coat it with seasoning, ship it out, declare quality/victory modern mass production" approach.

I got a gallon of ER from Tractor Supply for about $20.  I've heard that Harbor Freight also sells it, and I got a couple quarts from AutoZone before getting the gallon container.  I ended up using 1.5 gal inside a Tupperware plastic container to salvage the DO.

I first degreased the DO with Dawn detergent, hot water, & a Scotchbrite pad.  I didn't have any lye or spray oven cleaner at home to do a proper "scorched earth...burn it to the ground" degreasing job.  Maybe next time.

I then submerged the DO in the ER solution out in my garage (temps 40 F - 70 F this past weekend).  After leaving it overnight, the rust was very much gone.  Pitting was still evident, as were a few black streaks on the outside of the DO (remnants of baked on grease resistant to Dawn???), but the surface was a nice dull grey color, once I wiped off any nuked rust.  The converted rust had turned into a black sludge, easily wiped from the surface of the cast iron.

Remove it from the ER, wipe it off well, clean it under running water (with Scotchbrite), dry it in a 250 F oven...season with PAM at 500 F (with loving care...250Fx10 min wipe off excess...300Fx10 min...wipe off excess...cook 1 hr 500F)....verrrry niiiiiice!

I've got some pictures, but I'm away from home for ~10 days.  Needless to say, I suspect that my wife's best friend will be surprised & happy to see her resurrected DO.  So far, I've got 3 coats of seasoning on the base & 1 coat on the lid.

Now if she'll just USE IT!!!

As to whether ER will eat/dissolve iron itself, according to the info I've read on AlGore's Errornet (it's gotta be true.....right????)....NO. See: http://www.theruststore.com/Evapo-Rust-FAQ-W21C2.aspx

How does Evapo-Rust work?
Unlike other rust removers that use some type of acid to remove rust, Evapo-Rust works without acid. It will not attack the base metal, and it is safe to use. Evapo-Rust works through selective chelation. This is a process in which a large synthetic molecule forms a bond with metals and holds them in solution. Most chelating agents bind many different metals. The active ingredient in Evapo-Rust bonds to exclusively to iron. It will remove iron from iron oxide but is too weak to remove iron from steel where the iron is held much more strongly. Once the chelating agent has removed the iron, a sulfur bearing organic molecule pulls the iron away from the chelator and forms a ferric sulfate complex which remains water soluble. This frees the chelating agent to remove more iron from rust.

The stuff is not acidic (like Naval Jelly....thickened phosphoric acid) or strongly basic/caustic (like lye).  It's a chelating agent dissolved in water, along with some surfactants/soaps & other super-duper-secret ingredients.  No toxic chemicals at all, according to the MSDS.  I felt comfortable working with the stuff using my bare hands (no gloves).

Another decent web page re: Evapo-Rust is:  http://www.stovebolt.com/techtips/rust/evaporust/index.html

Even though I've been playing around with eeeeevil chemicals for 25+ years (degreed chemical engineer, plenty of industrial experience, blahblahblah), Evapo-rust interested me for a several reasons:

 - no need for a battery charger/electrolysis tank setup...no worry about hexavalent chromium from stainless or scraping away rust deposited on sheet steel during the electrolysis process

 - no (or minimal) need for caustic chemicals to degrease cast iron prior to processing

 - no worry about polarity as with electrolysis tanks...is the cast iron positive or negative or....

 - clean your cast iron, dump it in, let the stuff work...brush/wipe it off from time to time...let it keep working

Other than the cost, Evapo-Rust seems like a win-win solution to removing rust from your cast iron goodies.  It is not strongly acidic or basic...no need to neutralize it after use.  Just wipe/rinse off the converted rust residue, dry, season like normal.

[Jeff Johnson]

If you start with lye treated cast iron (no grease or crud buildup), you shouldn't need much scrubbing.  Maybe a gentle scrub with a nylon bristle brush at most.  For the dutch oven I treated, I used my hand to wipe the interior & used a Scotchbrite pad on areas of old crud buildup on the exterior/lip of the DO (I didn't use lye ahead of time).

Very easy....

[Tom Neitzel]

Thanks Jeff.  What I'm talking about is a light black-gray coating (the converted rust) that I have on the iron after the electrolysis process is done.  It's not hard to take off, I usually use warm soapy water and an SOS pad.  In most cases it just takes a moment or two, but with a waffle iron there are so many nooks and crannies that it takes a lot longer.  If something would do that final clean without leaving anything to wash off it would be nice for me anyway.

Tom

[Tom Neitzel]

Well, I got my gallon and am trying it out.  Here are some pictures to let you see.

This is my first test.  A little old waffle iron I just got from Germany.  Not too hard of a test.  Just some surface rust inside.

It is fresh out of the lye bath in the before pictures.  No scrubbing.

The after pictures are at the bottom.  You can see it was not too challenging.  The overall look is about the same.

Inside, it looks pretty nice.

I just rinsed it off in running water- no scrubbing :).

I've not put any oil on the piece in the after pictures.

I had not noticed some specs of something in the grooves inside, so I will put it back in the solution for a while.

This was immersed for about 4 hours.

Tom

[Tom Neitzel]

So I decided to try a tougher test.  I've had an old Leibrandt and McDowell style waffle iron laying around for several years that is quite rusty.  I had cleaned it in a lye bath then just didn't feel like finishing it.  It has some light and heavy rust.  These are the before pictures.  I put it in the solution yesterday at about 9:30 am, so the pictures of the solution below are after about 20 hours.  I'm going to rinse it off after 24 hours and see what I see.

I've included a couple pictures of the solution when I put it in yesterday (it's in a 9x13 oven pan sitting in a utility sink in the garage.  It is cool, around 55 degrees out there).

I've shown a picture of the solution this morning after 20 hours.  Those with good eyes might notice a pair of alaskan handles seem to appeared in the solution.

I decided to throw them in this morning to see how they clean up.  They're from a Revonoc iron I'm cleaning.  Before picture at the bottom.

Tom

[Tom Neitzel]

Here's my final report (this and the following message).  Here's my short conclusion with the detail in these two messages.

I love and hate the stuff.  It does have a place in my cleaning material stock.

First off we'll look at the Revonoc Alaska handles.  They were in the solution for 24 hours.  I took them out and just rinsed them off - no scrubbing.  Most of the chrome is gone (the dull areas) but they sure cleaned up nice without any real work on my part.  I would give Evapo Rust a 10 out of 10 for this result.  You can see the before at the bottom of the pictures in the previous message.

They look so nice - I might even consider re-chroming them.  Look how nice it even cleaned up the inside.  I've not coated them with anything in the picture - just rinsed in hot water and dried off.

Tom

[Tom Neitzel]

Now the hate part.

Here's the after photos for that old L&M style waffle iron that was so rusty.

I did rinse it off after 24 hours - didn't like the result and left if for another day (that's when I threw the alaska handles in).

I washed it off again after 48 hours with the result you see below.  Lots and lots of the rust has been removed, but there is still some left.

A gallon is supposed to clean the rust off 300 pounds of iron (generally).  When it turns icky black it is supposed to be used up.  My feeling is that this waffle iron had used up the solution and still not completely done.

I decided to throw the base in and see what would happen.  That's the last couple of pictures.

The solution didn't quite cover the base.  You can see the line in the side view.  Again, not all the rust is gone but it has removed a lot.

The picture of the bottom also shows a pretty striking line on the handle where it was and was not in the solution.

What I'm unhappy about is that this old waffle iron seems to have used up 1/2 of my gallon - far short of the 300 pounds cleaned.

I have a feeling it may be related to the quality of the cast iron, but I'm not sure.  I don't think it has attacked the cast iron but it would be tough to tell because this one was so rusty and pitted.

It certainly didn't affect the surface of my toy waffle iron or the coil handles.

I'm going to finish this piece in the electro tank.

My recommendation would be to use the Evapo Rust for those highly detailed, intricate items that can be a pain to scrub after the electro process like coil handles, and modern waffle irons.

I would run items through a lye bath then follow with the Evapo Rust.

I'm going to try the black solution again to see if it is still working.  Maybe put one of the Revonoc paddles in, or scare up something else.

I'm also going to try an old Norwegian krumkake iron I have.  Those made by Jotul, Mustad, Hammar and others had a pressed fiber handle riveted on.  I have an old tore up one that I'm going to put in to see it it attacks or softens the fiber.  I've been real leery of using electro or lye on these because of the submersion.

I might throw that waffle base in upside down to see if it will even out.

Tom

[Sandy Glenn]

Interesting experiment, Tom, thank you for posting details and pics.

A gallon is supposed to clean the rust off 300 pounds of iron (generally).  When it turns icky black it is supposed to be used up.  My feeling is that this waffle iron had used up the solution and still not completely done.

I'm going to try the black solution again to see if it is still working.  Maybe put one of the Revonoc paddles in, or scare up something else.  Tom

I'm wondering if you added some fresh solution to the icky black if it might juice it up somewhat?  Or would just the opposite happen where the icky black merely diluted and weakened the stronger fresh solution?  Just thinking out loud...

[Tom Neitzel]

I don't know.  I was thinking about pouring it through a coffee filter to see if anything comes out.  It really is black.  I've attached a photo of today's test.  It's a pre-WWII Mustad (yes, the fishhook people) krumkake iron.  These are the fiber handles I was mentioning.  I've been afraid to immerse them but these are pretty beat up so I'm going to try.  The rust is to test the solution.  It is so black that when it is immersed it is only 1/4 inch under the surface but you can't see it at all.

Tom

[Tom Neitzel]

Ended this experiment early.  It turns out the fiber handles don't like to be soaked so I stopped before they disintegrated.  I'm going to fill a plastic picture and stand the iron in it with the handles above the fluid.  It looks like it was starting to take the rust off.  Maybe black is OK.

I put that waffle iron in the electro.  I don't know what the Evapo Rust did to the surface, but it looks like I dropped an Alka Seltzer in the unit - it is bubbling so much so quickly.

Tom

[Tom Neitzel]

I know you've all been waiting with baited breath for my final report ;D

First, to John, technically I suppose I'm not part of the scientific community, but my degree is in Geology (MS, 72).  Worked one summer in the field but with the industry at a hiring low, I found an alternate career in systems analysis and computers.  Spent my career there, although Geology taught me how to use any tool in a systematic way to find answers.  I did faithfully watch Mr. Wizard growing up.  There are other threads here that can give you some ideas of what came of that (one episode with propane let my mom buy new curtains in the living room, but let's not get me started.

Back to Evapo-Rust.  I really like it.  I think it has a place in our cleaning repertoire.  Not for general use, but for those intricate, tough to clean items, and after at least a lye bath, or those "I've tried everything else and can't get it cleaned up things."

My solution is black as molasses but does indeed still work well.  I think there may be something about the composition of the old iron that made that waffle iron so tough to clean.

I bought a tall skinny container to continue testing with that rusty Mustad krumkake iron.  I'm just amazed with the results - I really never thought I would clean that puppy up.  If you look carefully on the handles you can see how far the solution covered them.  I didn't immerse the fiber handles.  I did try wrapping paper towels soaked in the solution to see if I could get the small line cleaned off but I finally decided to end the test - it might have cleaned a little more if I had left it longer.  I was even toying with soaking cotton balls in the solution and putting them on the rusty rivet heads to see if they would clean, but that will wait for another time.

Here's a series of pictures.  
Tom

[Tom Neitzel]

Here's the Mustad iron after.  Remember, I just took it out of the solution and rinsed it off.  No scrubbing, steel wool, or wire brush.

It almost seems like magic.

Tom

[Tom Neitzel]

Here's a closer picture of the handle area so you can see how well it did.  You can clearly see the line where the solution stopped.  Remember, the reason I didn't fully submerge it was that the fiber handles started to swell and absorb the solution.  Even though this one is pretty beat up, I didn't want them to turn into pulp.

Tom

[Tom Neitzel]

I got thinking about another claim that Evapo-Rust makes.  That is it will remove the bluing from gun barrels (supposedly any oxide coating).

I like to collect pizzelle irons.  Most of them are aluminum with steel handles.  I use a self-cleaning oven to clean aluminum.  I've learned to remove anything that is not aluminum before cleaning, particularly steel handles, because they may be discolored or otherwise damaged.

Here are some pictures of the aluminum Vitantonio pizzelle iron that taught me that lesson.  I took the wooden handles off but the steel handles discolored from the heat.  I tried scrubbing with steel wool to clean them up, but no luck.  This piece has sat on the shelf for many years to remind me of that.

So I figured, maybe the heat oxidized the steel.  Maybe Evapo-Rust would get it.

I put it in the solution overnight.  It cleaned up a bit after I rinsed it off.  I then buffed lightly with an SOS pad and VIOLA:o, they looked good as new!  Shiny steel restored!

I even put the wooden handles back on.

The pictures go from before to after.  The one at the bottom is what the inside looks like if you are curious.  It makes 3 wafers that are about 3.5 inches each, longest dimension.

As I said earlier, I'm keeping this product around.  It sure would be interesting to know what it is.

Tom

[Jeff Johnson]

I need to get a tall/thin container for doing skillets.  The Tupperware bowl/lid combo is fine for doing smaller dutch ovens & such, but doesn't work well for larger items.

I was very pleased with Evapo-rust and how well it worked on my wife's friend's cast iron.  I've got about 4 layers of seasoning on it now, and it's looking pretty nice.  I've got a knife blade soaking in the Evapo-rust now, and expect that it should remove surface rust from the bead blasted blade (Benchmade/Emerson CQC7).