Home made "Evaporust" formula

[rcx132]

I came across this video, a famous YouTube gunsmith has published a rust removal recipe that uses the same chemical mechanism as Evaporust. For those who don't know, EvapoRust uses chelation instead of acid and has the advantage of not damaging the base metal. It works great but is very expensive. This guys formula is slightly acidic but a fraction of the cost and lasts longer.

I've watched this YouTuber before, he comes across as honest, so worth trying his mix.

 

[Screwdriver]

Yeah saw that and am mixing up a batch today. Probably use SLS as the surfactant.

 

[rtcosic]

I have all those ingredients so I'll make up a 5 litre batch. I also have some solid fuel blocks which supposedly act as an inhibitor so I'll add one to the mix.

EtA: I saw that video on the day it was posted but as I didn't know the poster and it referred to firearms I assumed it was just more 'Mercan clickbait rubbish talking of non-brewed condiment or molasses.

That'l larn me!

 

[rtcosic]

SLS

SLS? Too many options for Mrs Google to help.

I was planning on using Lidl's best floor cleaner detergent - my default cleaner.

 

[Beanwood]

Yeah saw that and am mixing up a batch today. Probably use SLS as the surfactant.

I'll be very interested in your results!

 

[Jelly_Sheffield]

SLS? Too many options for Mrs Google to help.

I was planning on using Lidl's best floor cleaner detergent - my default cleaner.

Sodium Lauryl Sulphate, also known as Sodium Dodecyl Sulphate.

Super common ingredient in anything that needs surfactant, and cheap as chips.

 

[Morris]

Sodium Lauryl Sulphate, also known as Sodium Dodecyl Sulphate.

Super common ingredient in anything that needs surfactant, and cheap as chips.

It's in toothpaste!

 

[rcx132]

Yeah saw that and am mixing up a batch today. Probably use SLS as the surfactant.

Be sure to let us know what you find !

 

[Agroshield]

Any chance to write down the recipe here in the forum. That will save us all watching the same video. Thanks.

 

[123hotchef]

Dam right we need a recipie

 

[Misterg]

Any chance to write down the recipe here in the forum. That will save us all watching the same video. Thanks.

It's (home made) sodium citrate:

"To each liter of water, I’m adding 100grams of citric acid and 40 grams of sodium carbonate, also known as washing soda.

[...]

The same result can be obtained using different amounts of sodium bicarbonate, also known as baking soda, or sodium hydroxide, also known as caustic soda. For 1 liter of water and 100 grams of citric acid, you’ll need either 40 grams of washing soda, or 63 grams of baking soda, or 30 grams of caustic soda.

[...]

We just want to add one more ingredient, to act as surfactant. I’m using regular dish soap, in somewhat arbitrary amounts..."

 

[Blobber]

So for the thick people like me whats going to be the difference between this and straight citric acid/water mix??

 

[LewisT]

So for the thick people like me whats going to be the difference between this and straight citric acid/water mix??

The sodium carbonate make it more ph neutral so it wont eat the good metal as much.

 

[Screwdriver]

Let the games commence...

SLS - Check! Acts as a surfactant to allow the solution to wet the surface. I think it breaks down the tendency to form a meniscus and is something professional bulle blowers know all about. It's the stuff they put in soap to make it foam!

I was using it when trying to reconstruct the formula for Nitormors.

Bicarb I get by the sack load for vapour blasting (and killing moss), also useful for electrolysis.

...and of course citric acid. I get through a LOT of that.

So what's the thing with sodium carbonate/bicarbonae? Well it stops the acid from attacking the metal. I have never had an issue with that but then again, I have never really looked. Comes out clean, jobs a goodun. But adding sodium bicarbonate is a chelating agent which reduces the PH of the acid so that it won't attack the metal while still reducing the rust.

I assume (soon find out) that since the acid no longer reacts with the metal, it also allows the solution to remain active for longer.

Anyhow, there's a short funny video coming up next. How is it funny? Soon find out...

 

[Screwdriver]

 

[Screwdriver]

...and ten minutes ago, I dunked this in there.

 

[Screwdriver]

Half an hour later:

I left one bit out so you can "spot the difference"

TBH, citric alone would do that I think. That's more citric than I would normally use per litre but if it lasts longer then that's a big win.

 

[julianf]

If you put caustic soda with Citric acid, you will get acid+base>salt+water

Ie no acid left.

 

[Screwdriver]

If you put caustic soda with Citric acid, you will get acid+base>salt+water

Ie no acid left.

Presumably then, the relative concentration must be key in producing a "working" formula.

No doubt at all that this concoction does indeed work.

Whether or not it is "Evaporust"...

 

[Blobber]

Half an hour later:

I left one bit out so you can "spot the difference"

TBH, citric alone would do that I think. That's more citric than I would normally use per litre but if it lasts longer then that's a big win.

So for just a citric acid solution whats the shelf life like, how long does it last?