Citric acid derusting

[Onoff]

What process shall I follow up with once de-rusted?

All the stuff I am doing is running gear on a car. I am thinking a kind of primer (etch?) and paint. Will use VHT stuff as I have brakes too.

Be really careful to rinse and rinse again. Don't want any acid leeching out later. I think you can make sure of neutralising with bicarb or something?

I bought a MK1 Focus estate rear cross member. It wasn't too bad when I got it but it sat on trestles in the garden under a tarp for a good while. I eventually then took off all the trailing arms etc and put it in the bath of citric...in Nov 2019. I'm taking it to the tip Thursday I think.

 

[conor1n]

Be really careful to rinse and rinse again. Don't want any acid leeching out later. I think you can make sure of neutralising with bicarb or something?

I bought a MK1 Focus estate rear cross member. It wasn't too bad when I got it but it sat on trestles in the garden under a tarp for a good while. I eventually then took off all the trailing arms etc and put it in the bath of citric...in Nov 2019. I'm taking it to the tip Thursday I think.

Did you leave it in the Citric acid for a year and a half? Or put it in bath, then took it out without neutralising and the acid drew the moisture from the air?

Good point on sodium bicarb..

 

[Barking Mat]

Did you leave it in the Citric acid for a year and a half? Or put it in bath, then took it out without neutralising and the acid drew the moisture from the air?

Good point on sodium bicarb..

What was the sodium bicarb tip? I missed that.

 

[conor1n]

What was the sodium bicarb tip? I missed that.

Oh I misread.. he said, bicarb. I assume Sodium Bicarbonate (Baking soda) to neutralise the acid after dipping so it doesn't continue to draw moisture out of the air? I guess it's hygroscopic?

 

[Ross365]

Deox-C instructions attached as a PDF. I think it's been discussed before but Deox-C some think has some secret ingredient to give in the edge. My money's on a detergent of some kind. I keep meaning to add some Fairy Liquid to see if that affects the process.

Adding some kind of wetting agent (alcohol ?) or detergent may be useful, but I'd stay well away from washing up liquid. That is full of salt (sodium chloride) and chloride is brilliant at initiating corrosion, and is damn hard to wash off metal. There are compounds similar to citric acid (eg EDTA) which might improve performance but will probably increase costs too .

 

[Onoff]

Did you leave it in the Citric acid for a year and a half? Or put it in bath, then took it out without neutralising and the acid drew the moisture from the air?

Good point on sodium bicarb..

I left it in the bath for a year and a half...

Even when I dipped it the first time and things were looking quite good I felt the metal maybe a bit thin in places. Tbh I couldn't think how to preserve it when it first came out & I didn't want to spend real money on expensive paint. I debated hitting it with the cold galv spray I like...but didn't.

Then:

So I just dropped it back in and forgot all about it.

& now:

 

[bigegg]

I left it in the bath for a year and a half...

Even when I dipped it the first time and things were looking quite good I felt the metal maybe a bit thin in places. Tbh I couldn't think how to preserve it when it first came out & I didn't want to spend real money on expensive paint. I debated hitting it with the cold galv spray I like...but didn't.

View attachment 283019

Then:

View attachment 283016

View attachment 283017

So I just dropped it back in and forgot all about it.

& now:

View attachment 283009

As I said before:
Drop it back into some fresh and see how it comes out.
You might be pleasantly surprised.

 

[Onoff]

As I said before:
Drop it back into some fresh and see how it comes out.
You might be pleasantly surprised.

Means I've got to buy another 20kg of citric!

Anyone know the weight of a MK1 Ford Focus rear subframe? I could maybe gauge the metal percentage lost.

 

[conor1n]

Hi guys,

So I have a few bits small bits (test subjects) in the bucket now. They are done and need to come out, but I don't have anything to put on them.

What do I need. There will be brake components too, so I am thinking some kind of VHT primer and paint. I'm not 100% sure what colour yet so is the primer enough to keep out moisture? I remember hearing before that you need epoxy primer to resist moisture, but not sure if that is available VHT. Also, where does etch primer fit into this?

What should I do?

On the other hand, I might just neutralise them with baking soda dry them and give them a lash of wd40 for now. But I still need to know the best process you guys would recommend, what do ye think?

I guess I need to read up on the types of paints for metal that prevent rust.

 

[Kram]

Rinse/dry the parts and they will be fine. Ive only had one out of 20 peices rust after and it was extremely light.
Those brake discs I wouldnt have dipped, just use as is and they would clean up within 100 meters.

 

[conor1n]

Rinse/dry the parts and they will be fine. Ive only had one out of 20 peices rust after and it was extremely light.
Those brake discs I wouldnt have dipped, just use as is and they would clean up within 100 meters.

Thank you. Those brakes were well and truly caked with rust outside of the contact area too.

 

[Onoff]

Cheers @bigegg that's £25 gone on another 10kg of citric.

 

[ronan]

I tried to buy citric acid over here and couldn't find any, turns out the drug dealers use it for something to do with their trade. It doesn't bother them, just the people who use it legally .

 

[Onoff]

I tried to buy citric acid over here and couldn't find any, turns out the drug dealers use it for something to do with their trade. It doesn't bother them, just the people who use it legally .

Try some full fat Pepsi (as opposed to Coke). Pepsi has citric acid in. Don't think coke does.

 

[Monkey Harris]

Try some full fat Pepsi (as opposed to Coke). Pepsi has citric acid in. Don't think coke does.

Vinegar is much more effective than cola...
I've tried both....

 

[Onoff]

Vinegar is much more effective than cola...
I've tried both....

What vinegar? Do you keep it warm?

I might try it, got a jar of pickled onions to finish...

 

[conor1n]

I tried to buy citric acid over here and couldn't find any, turns out the drug dealers use it for something to do with their trade. It doesn't bother them, just the people who use it legally .

I ordered mine from a place called Bomar in Wicklow that sell soap making supplies.

I bought 1 kg for about 5 euro.

Citric Acid

Description Citric Acid available in 500g tubs, 1kg tubs, 5kg tubs and 25kg sacks. Technical Documents Certificate of Origin Product Specification Food Safety System Certificate Feed Certificate Halal Certificate Kosher Certificate Information Pack Certificate of Quality Certificates of...

bomar.ie

 

[ronan]

I ordered mine from a place called Bomar in Wicklow that sell soap making supplies.

I bought 1 kg for about 5 euro.

Citric Acid

Description Citric Acid available in 500g tubs, 1kg tubs, 5kg tubs and 25kg sacks. Technical Documents Certificate of Origin Product Specification Food Safety System Certificate Feed Certificate Halal Certificate Kosher Certificate Information Pack Certificate of Quality Certificates of...

bomar.ie

Thanks Conor, i just bought a large bag of it off ebay UK and had it delivered to Parcel motel. Haven't used it much since but at least i have it there if i need it. It was the same with Borax when the sisters little one went through the making slime fad a few years back. Couldn't buy it here. Ditto nitric acid or copper sulphate, but i reckon the wallys in brussels have something to do with that.

 

[Onoff]

10kg from here:

142887803548 for sale | eBay

Find great deals on eBay for 142887803548. Shop with confidence.

www.ebay.co.uk

 

[Monkey Harris]

What vinegar? Do you keep it warm?

I might try it, got a jar of pickled onions to finish...

Bookers cheapest ...gallon jugs about £4