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· Senior junior member
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On Tuesday afternoon, I put some items in a container of evaporust. They included a plane casting, two frogs, a blade and cap iron, two lever caps and an old crescent wrench. All had rust to varying degrees. Wednesday I checked on them in the morning and they looked pretty good, but I didn't have time to deal with them at all that day. This afternoon I took the pieces out, flushed them in water and dipped them back in the evaporust per the instructions. None of the parts looked as good as they did on Wednesday. Even the bright metal (except the chrome parts) that had been bright before, took on a dingy, yellowish cast.

I'm thinking maybe I should let it all dry and then try again. Anyone got a better idea?

TIA
 

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I'm thinking maybe I should let it all dry and then try again. Anyone got a better idea?

TIA
I would not put them back in Evapo-Rust.

My experience is that both Evapo-Rust and oxalic acid (aka wood bleach) will eventually put a film on many of the pieces. The good news is that this means the rust removal has completed.

The Evapo-Rust film is normally a dull grey, although some of my pieces had a black film.

The oxalic acid is a yellowish film.

In both cases the films do not wash off. They are easily removed with fine brass wire brush, or e.g. 600 grit wet-dry paper.

The Evapo-Rust black film takes a bit more effort to remove.
 

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There are several threads here where electrolysis is explained. I've got a bookmark for a couple of sites but I can't find them - google electrolysis for rust removal and you'll find several.

I can't use my battery charger as it has an electronic sensor that senses a short and turns it off, but if you have an older/non-digital charger it should work. I use a power supply for a laptop that I've spliced into for my electrolysis. It doesn't work as fast as a charger might as it's only 3A, but it's done the job for everything I've thrown at it in under 24 hours.

Most guides to electrolysis say to use sodium carbonate (washing soda), but I haven't been able to easily find any, so I use sodium bi-carbonate (baking soda) instead. It might be a little slower, but who cares - most times I've had to leave my bath overnight anyway.

Just make sure if you are going to try electrolysis that you have the electrodes hooked up with the correct polarity or you'll ruin your parts very quickly!
 

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And make sure your item to be derusted and your sacrificial anode are connected correctly. Otherwise, your precious item will become completely ruined and the sacrificial anode will be sparkling clean.

Don't ask how I know this. It is still too painful.

Greg
 

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On Tuesday afternoon, I put some items in a container of evaporust. They included a plane casting, two frogs, a blade and cap iron, two lever caps and an old crescent wrench. All had rust to varying degrees. Wednesday I checked on them in the morning and they looked pretty good, but I didn't have time to deal with them at all that day. This afternoon I took the pieces out, flushed them in water and dipped them back in the evaporust per the instructions. None of the parts looked as good as they did on Wednesday. Even the bright metal (except the chrome parts) that had been bright before, took on a dingy, yellowish cast.

I'm thinking maybe I should let it all dry and then try again. Anyone got a better idea?

TIA
Put parts in boiling water if evaporust is caked on. Oxalic is water soluble
 

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White vinegar works well and is pretty cheap and environmentally friendly. You can even strain the crud out of it, store it, and re-use it until it doesn't work any more. I've even used it to sharpen old worn out files and rasps. Amazing!
 

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There are several threads here where electrolysis is explained. I've got a bookmark for a couple of sites but I can't find them - google electrolysis for rust removal and you'll find several.

I can't use my battery charger as it has an electronic sensor that senses a short and turns it off, but if you have an older/non-digital charger it should work. I use a power supply for a laptop that I've spliced into for my electrolysis. It doesn't work as fast as a charger might as it's only 3A, but it's done the job for everything I've thrown at it in under 24 hours.

Most guides to electrolysis say to use sodium carbonate (washing soda), but I haven't been able to easily find any, so I use sodium bi-carbonate (baking soda) instead. It might be a little slower, but who cares - most times I've had to leave my bath overnight anyway.

Just make sure if you are going to try electrolysis that you have the electrodes hooked up with the correct polarity or you'll ruin your parts very quickly!
Washing Soda is simply Sodium Hydrochloride (a nasty burn if you are not careful) either way one must put plenty of cold water in a tub BEFORE adding soda or Sodium Hydrochloride AKA Caustic soda. Make sure you have a clean piece of iron that is as large as , or larger than the item you want to clean. Be aware that during the electrolysis phase the red iron oxide will be removed and replaced by black iron oxide which then acts a preventative to further rusting. An older battery charger that is without electronic controls is the best and you can run it at 12 amps without a problem. It is very active process. Wear Rubber gloves, eye protection and don't breathe the fumes -- in other words don't hang your face over the tank and do it in a well aerated area. Baking soda works well as an adjunct to Caustic Soda, it slows down the process a little and doesn't work quite so actively. I am writing from experience.
 

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Washing Soda is simply Sodium Hydroxide NaOH. (a nasty burn if you are not careful) either way one must put plenty of cold water in a tub BEFORE adding soda or Sodium Hydroxide AKA Caustic soda. Make sure you have a clean piece of iron that is as large as , or larger than the item you want to clean. Be aware that during the electrolysis phase the red iron oxide will be removed and replaced by black iron oxide which then acts a preventative to further rusting. An older battery charger that is without electronic controls is the best and you can run it at 12 amps without a problem. It is very active process. Wear Rubber gloves, eye protection and don't breathe the fumes -- in other words don't hang your face over the tank and do it in a well aerated area. Baking soda works well as an adjunct to Caustic Soda, it slows down the process a little and doesn't work quite so actively. I am writing from experience.
 
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