I've heard all sorts of claims about the stuff, but the $30/gallon price tag always put me off.

A few items on the new-to-me lathe need serious cleaning and I had a $20 credit at Tractor Supply so I splurged on a gallon.

Wholly Bat, Shitman! That stuff REALLY works! An hour in the bath, wipe it off with water and a damp sponge and dry it good. Right down to clean metal. Easy-peasy.

Two Thumbs Up and the PHPaul Stamp of Approval!

I agree. Finding Evapo-Rust was a revelation for me.

Thanks for the heads up, never heard of it till now.

In my recent foray into the world of the ultrasonic cleaner, I found some videos of guys using this stuff in ultrasonics for cleanup of stuff left outside for years. It's pretty amazing.

Wish I'd known about this when I had the Lotus.
Treated nearly the whole chassis with Ospho, then had the chore of scraping all the scale off the metal. Left it very clean, but was a lot of work, and required some good ventilation.

Amazing stuff. Found my fence pliers buried in the soil on the side of the house. Rusted shut. Tried Evapo-Rust and the results were unbelievable.

I'll keep that in mind. Sounds like great stuff!

What's the chemistry behind it?

quote:

Originally posted by Keystoner:
What's the chemistry behind it?

Inositol hexaphosphoric acid.
I've used diluted phosphoric acid before but it leaves the metal black, like vinegar does.

^^^ Me too, SC. A product we referred to as Ospho.

It also works really well to restore the effects of rust & varnish on the interior of a neglected motorcycle tank.

I've used it before with mixed results, it apparently may remove other finishes in addition to rust.

Does anyone know if it will remove a hot dip galvanized finish ? I have some parts i'd like to de-rust, but only if it would leave the galvanized coating alone.

FWIW:


“HOW DOES EVAPO-RUST® WORK?

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 iron exclusively. It can remove iron from iron oxide, but is too weak to remove iron from steel because the iron is held much more strongly.”



“EVAPO-RUST® will remove sacrificial oxide coatings and is perfect for removing weapon finishes such as Bluing, Parkerizing, Zinc Phosphate, and Browning.
Other coatings such as Anodizing, Cobalt Tungsten Carbide, Powder Coating, Chrome, Nickel and Paint will not be removed as long as they do not contain oxides and are still adhered to the surface. EVAPO-RUST® will not harm lead or solder points.


ARE THERE ANY METALS I SHOULD NOT SOAK IN EVAPO-RUST®?

EVAPO-RUST® is not recommended for use on magnesium or magnesium alloys.


CAN I USE EVAPO-RUST® TO CLEAN BRASS, COPPER, AND/OR ALUMINUM?

It depends on what you are trying to remove. EVAPO-RUST® will not damage any of these metals and will clean oils and other soils. However, it will not remove corrosion from them. It is designed to remove rust (oxides of IRON). So if you have an iron containing part that is rusted and also has aluminum or brass or copper, etc attached, then you can soak the whole thing. If you have a part that does not contain iron and is not rusted, then why would you want to use EVAPO-RUST®?“


https://orisonmarketing.com/pages/evapo-rust-faq

quote:

Originally posted by wrightd:
I've used it before with mixed results, it apparently may remove other finishes in addition to rust.

Does anyone know if it will remove a hot dip galvanized finish ? I have some parts i'd like to de-rust, but only if it would leave the galvanized coating alone.

It most likely will remove areas of hot dipped zinc, or any other coating/plating/treatment where iron oxide (rust) may be underlying.

And almost anything that has rust, has hidden rust in places beneath.

I say this because I use 9:1 water and molasses as a chelating agent for large steel, iron, cast iron pieces. It works as Evaporust, but takes a little longer and much cheaper for large volume.

I dropped a rusted chain with hooks ( 10 feet length) in a bucket and when I pulled it out, and started rinsing, it was "silver and speckled black". Where the zinc was removed in spots.

Anything that is coated, painted etc. likely will be "mottled".

If I am going to the point of using something to remove rust, I am beyond concern with any applied finish and will be doing my own when the process is complete.

(Mostly tools and old car parts I am reconditioning)

I also find using a steam cleaner and various cleaners/solvents to remove grease and oil helps prevent "souring" of Evaporust/Molasses solution as well as preventing the solution from the barrier action of grease/oils.

quote:

Originally posted by ScreamingCockatoo:

quote:

Originally posted by Keystoner:
What's the chemistry behind it?

Inositol hexaphosphoric acid.

Oh, shit! Keystoner said the C-word!



Hell of a good metal chelating structure. EDTA (Ethylenediaminetetraacetic acid) is a more common one (structure below). Chelating agents basically take up (or bind with) metals in solution.



When put into water, molecules like these will loose many of the hydrogens (protons!), a process that can be referred to as deprotonation. This leaves lots of negatively charge sections that attract the typically positive metal ions. The complex molecules wrap around the positively charged metal ions in a water solution. The more negatively charged sites, the more metals stick and the stronger they stick.



Wuuuuh?? SCIENCE, BRO!

Theres a guy on You Tube called Handtool Rescue. Evapo rust is all he uses. Its amazing how good that stuff works.

ON the other hand for around $10.00 you can get Loctite Naval jelly. Works great.

Glad to see some like it. Didn't please me on a trailer. Went back to OSPHO.

Having some experience with rust removal, some notes:

1. I suspect Evapo-Rust works best on clean (no oil/grease/scale) objects with surface rust. It was perfect for cleaning up lathe parts. The advantage here is quick cleanup and no blackening/coating.

2. Similar to #1, the various sorts of gel-based phosphoric acid stuff (I like Rustoleum's product) are better for heavier rust, large objects that can't be conveniently immersed and things you want to clean up in place.

3. Removal of grease and scale is important in ANY de-rusting procedure. Thorough clean up and flash rusting prevention is also key.

4. Electrolysis works well and is the most economical: Water and washing soda. One is free and a lifetime supply of the other is about $5

My son put me onto this stuff.

Worked wonders on the pruning shears left out in the rain (not by me!)

For a chemical that did so much so quickly, it seemed pretty bland to this non-chemist. Followed instructions as always - giving chemicals their due is Standard Operating Procedure - but was pleasantly surprised that there was no harsh smell and that cleanup/storage was straightforward.

It also removes gun blue quite effectively if you are planning a refinish.