First attempt at citric acid bath cleaning.

[Barking Mat]

Well, first time, never tried before, seem some fine results from people on here, so thought I'd give it ago.

My Yost vice, before.

Then cup brush on thé a

25 litres of very hot water, some other bits too, spanners etc. And 25 scoops of citric acid powder.

That was an hour and a half ago, looking forward to results tomorrow.

Questions...

Can I reuse the solution ?

Been recommended to phosphoric acid it before painting?

 

[Pigeon_Droppings2]

I keep using the same bath until it stops working ....heat would speed things up but if like me you don't mind just leaving it I think it's fine as it is.

I like citric acid because its one of the safest ways of removing rust I think....I just give the parts a good wash and thats all I do.

 

[Screwdriver]

Yes, I reuse mine until it is either too dirty or weak. It should be stored in an airtight container, in a cool place out of sunlight.

 

[optima21]

It should be stored in an airtight container, in a cool place out of sunlight.

sounds like those are the instructions with it being food grade

 

[Screwdriver]

sounds like those are the instructions with it being food grade

Well, yeah. Otherwise it goes off and gets eaten by bugs and fungi. While that may be dangerous I don't mind that so much as the fact it also loses its acidity.

 

[Barking Mat]

Well it's in an air tight container, at work in the workshop, might warm up by May?

 

[Barking Mat]

I keep using the same bath until it stops working ....heat would speed things up but if like me you don't mind just leaving it I think it's fine as it is.

I like citric acid because its one of the safest ways of removing rust I think....I just give the parts a good wash and thats all I do.

You just rinse and leave it to dry, then paint?

Or wipe down with oil?

Curious what to do.

 

[Screwdriver]

In the past I have cleaned, dried and applied linseed oil on the grounds that an oil based paint will happily stick to linseed oil anyway.

Don't know how true that is because after applying boiled linseed oil I have often decided that's the finish I want .

 

[The_Yellow_Ardvark]

You just rinse and leave it to dry, then paint?

Or wipe down with oil?

Curious what to do.

Dry well.
Place on your aga.

Or a hot air paint stripper.
You will soon see the damp being driven out.

Paint, up to you.
Wax and oild will being up the metal a treat.

 

[Pigeon_Droppings2]

I tend to wash them down and dry them good under the heater...then panel wipe and either etch prime or I use my rc900 converter if I'm going to be leaving them a while until I paint as it stops the flash rust.

 

[Barking Mat]

I was told phosphoric acid blackens the steel, and gives it an etch surface for paint.

Linseed oil, boiled? Eh? What kind of finish does it give @Screwdriver ?

 

[Barking Mat]

Dry well.
Place on your aga.

Or a hot air paint stripper.
You will soon see the damp being driven out.

Paint, up to you.
Wax and oild will being up the metal a treat.

Oiled then waxed? Or waxed then oiled?

I tend to wash them down and dry them good under the heater...then panel wipe and either etch prime or I use my rc900 converter if I'm going to be leaving them a while until I paint as it stops the flash rust.

This is my concern, I've cleaned stuff up before, wiped with oil, then a month or so later, it's rusting.
Yep, I need advice on rust proofing metal, I like paint, but sometime raw metal looks best, without the rust.

 

[Barking Mat]

Yes, I reuse mine until it is either too dirty or weak. It should be stored in an airtight container, in a cool place out of sunlight.

Query, the powder, or the used solution? Thanks.

 

[Screwdriver]

I was told phosphoric acid blackens the steel, and gives it an etch surface for paint.

Linseed oil, boiled? Eh? What kind of finish does it give @Screwdriver ?

Bit llke this:

Looks amazing on cast iron with a sort of soft sheen.

 

[RaceDiagnostics]

Just a bit of feedback from my experience, some steels come out fairly clean, others come out covered in a black residue. If it comes out black, wash it down immediately in hot soapy water and scrub with a scotch pad. That will take off the black.

PS I always wash and degrease thoroughly before dipping in the citric. Don't know if citric and detergent in together will work.

 

[TechnicAl]

I was told phosphoric acid blackens the steel, and gives it an etch surface for paint.

Linseed oil, boiled? Eh? What kind of finish does it give @Screwdriver ?

Phosphating is good as a base for paint....Phosphporic Acid passivates or phosphates the surface....not too much though or it goes dusty and you will get the opposite effect.........Most uncoppered MIG welding wire is phosphated....its also a good lubricant base.......a lot of wire is phosphated and boraxed before drawing as it passivates and provides a base for the lubricant.

 

[Screwdriver]

Or this:

 

[Barking Mat]

Bit llke this:

Looks amazing on cast iron with a sort of soft sheen.

That's a nice finish, similar on steel?

Just a bit of feedback from my experience, some steels come out fairly clean, others come out covered in a black residue. If it comes out black, wash it down immediately in hot soapy water and scrub with a scotch pad. That will take off the black.

Thanks, good to know.

Phosphating is good as a base for paint....Phosphporic Acid passivates or phosphates the surface....not too much though or it goes dusty and you will get the opposite effect.........Most uncoppered MIG welding wire is phosphated....its also a good lubricant base.......a lot of wire is phosphated and boraxed before drawing as it passivates and provides a base for the lubricant.

We've an industrial quality large can at work, so mix up a weak solution and experiment, thanks.

Or this:

And that prevents rust in a normal environment. Do like that. Thanks.

 

[Screwdriver]

Before and after for comparison. This was derusted in a (large!) electrolysis tank and the plain surfaces are wire wheeled and treated with blo,

 

[MattF]

Any flash rust will usually wipe off. Pour boiling water over the pieces once you remove them & give them a quick dry down. A little bit of flash rust is of no detriment.

Linseed oil gives a nice finish in itself, & is also a perfect base for paint.