Rust Removal and Prep CITRIC ACID

[woody28A]

G'day Peter,talk to me on Sunday and I'll give you some details.

[Sly Fox]

Thanks Woody

[41 Willy PU]

Has anyone tried the white knight concrete etcher?. Does citric acid effect rubber?. I have some surface rust on the bottom of some running boards and was wondering if I could put the whole lot in a citric acid bath. Thanks

[cdansie]

Has anyone tried the white knight concrete etcher?. Does citric acid effect rubber?. I have some surface rust on the bottom of some running boards and was wondering if I could put the whole lot in a citric acid bath. Thanks

White Knight concrete etcher works great. I bought some from Bunnings after reading on here and and very pleased with the results. It is a bit more expensive than buying in bulk but it was convenient for me.
Haven't tried anything with rubber on it though

Chris

[Sly Fox]

Has anyone tried the white knight concrete etcher?. Does citric acid effect rubber?. I have some surface rust on the bottom of some running boards and was wondering if I could put the whole lot in a citric acid bath. Thanks

White Knight concrete etcher works great. I bought some from Bunnings after reading on here and and very pleased with the results. It is a bit more expensive than buying in bulk but it was convenient for me.
Haven't tried anything with rubber on it though

Chris

Hi Chris,

What water to concrete etcher ratio did you use?

Cheers,
Peter

[cdansie]

I mixed the 1kg with 15litres of water
Chris

Code: Select all

[igotae21]

Thought I'd add my experience in for discussions sake.

I used oxalic acid instead of citric acid. This stuff is 100% oxalic acid, but I'm sure there's alternatives: http://www.bunnings.com.au/cleaner-bric ... r_p0960276

Citric and oxalic acid are both chelating agents apparently, meaning they bond with rust rather than react with it (like phosphoric acid does). They're both safe on chrome for this reason because they'll only bond with and lift away the rust, rather than eating away base metal as well. I'd use either without a worry.

So this is what I did - I had some chrome bumpers from an '81 BMW I'm restoring which had heavy rust on the back, but only some light spots coming through the chrome on the front.

IMG_0188_zps7ccd7a50 by igotae21, on Flickr

IMG_0186_zpsd067f1b1 by igotae21, on Flickr

I mixed up a solution (1% by volume) with oxalic acid powder and soaked the bumpers overnight:

P3020006_zpse65ea708 by igotae21, on Flickr

And this is what I ended up with:

P3020008_zps24009074 by igotae21, on Flickr

P3020021_zps2572574b by igotae21, on Flickr

P3020022_zps57559bb3 by igotae21, on Flickr

P3020013_zps038d8aa5 by igotae21, on Flickr

I was happy with it, and it takes such little effort. If you don't clean off all the dirt and oil from your item before soaking, you'll get more of the yellowish film that you can see in some of the pictures, but its easy to wash off with a soft brush and some soapy water if its not left too long.

Just need to paint the backs and oil/wax the chrome to seal.

[lowxm]

so I've been trying to find where to buy citric acid, i came across this company http://www.consolidatedchem.com/p_food.html

gave them a call and the bloke says they have it, $6.50/kg +GST
not the cheapest but they do have it

also Elders farm supplies in caboolture have 25kg bags for $75

[Grazza]

Digging up an oldie but a goodie, just wanted to share this with you,



At $18.30/Kg it is a tad cheaper than the White Knight product if you're doing smaller jobs. As you can see I'm not doing a small job, but it's all I can get, without driving to Brisbane or paying through the nose for freight. I have used 8 tubs to do the body of my '27 Tudor. Have the rear panel to go and it is still working fine, although taking a little longer than at the start. Got it from the Big Green Shed.

[jailbar joe]

back to the top for eric

[Extreme E]

back to the top for eric

Thanks Joe. That was an informative read.
Eric

[78corvette]

Tried the citric acid from the supermarket in about a litre of water & left plates for about a week found they had all developed a white crystal growth which had bonded them together all cleaned up ok with wire brush & fresh water just wondering what I did wrong was solution too strong or did I leave them in too long ?

[Chrisso]

I'm probably wrong ( I will get told if I am) but in my experience with citric acid only this build but lots of other stuff including aluminium, its a bit of both I usually check it and give the parts a bit of a pressure wash after 1 or 2 days if there are any crystal formations I just add some hot water until they are dissolved and it usually turns out great, only my experience mind. Most of my Pilot bits have spent a holiday in the citric.

[Mudgy]

I'll only use it on steel, after most of the paint, and ALL the gunk is taken off first. Alloy bits (for me anyway) are small enough to whack in the sandblaster ay my Dad's place

[Extreme E]

Over three weeks I have cleaned 3 batches of body panels for the next Willys project..
The very heavy surface rust cleaned up nicely. Some paint came off too.
I used 25kg bag of acid per 1000 litres and left parts in there for 6-8 days.
I pressure cleaned them afterwards and treated them with Por 15 Metal Ready.

So far so good. I have a chassis in there at the moment.

EE