# HELP! Cement dried on paintwork



## Cy-Zuki

Hi Mike,
During the red hot summer here in Cyprus I must have driven through a puddle of cement or similar. I soon noticed the mess on the lower sill but it had probably been there two or three days and baked hard in our hot sun.

I have kept ignoring the problem, but as spring approaches I want to get the car back to good order before applying a nano coating.

It is difficult/impossible to photograph on my white car. I feel if I just use a foam pad, it will get torn to shreds on the rock hard spikes of cement. 

Can you offer any advice on how I could go about removing this please? I am tempted to really soak it and then try and gently scrape it off but am too scared!

Thanks,
Geoff


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## steelghost

Use a mild acid. Some strong vinegar would be a good place to start.


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## Hereisphilly

Or if you can get your hands on some AS Congo that'll do the trick

Sent from my XT1635-02 using Tapatalk


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## Cy-Zuki

Hmmmm tried vinegar - made no difference???? 

Maybe it was some sort of exterior coating for a house or a plaster additive?? Don't think they do any AS out here sadly.

Geoff


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## DLGWRX02

Do you have a builders merchants, you may be able to get something there to dissolve cement. I know my father in law uses something on his tools (hes a builder) to dissolve dried on cement. No promises it won't cause any reaction to paint but if your careful with application, it has to be better than leaving it on.


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## Cy-Zuki

Good idea DLGWRX02, I before posting I searched the forum and someone had recommended a product from Screwfix but getting a liquid sent over to Cyprus is a bit difficult.

Geoff


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## SunnyBoi

Vinegar will work but it needs some time to act. Wet tissues with vinegar and stick them on the cemented portions. After 15 minutes, you should be able to crumble the cement with your fingers.


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## Mcpx

Plain old cement does not play well with water so first step for me would be to soak it, although you need to make it wet and keep it wet for some time depending on how thick it is. Give it a good soaking and then cover it with a wet towel and keep the towel wet, if it's just a thin layer it may loosen in a couple of hours but any thicker and you could be talking days before it has any effect. If you agitate it then you are risking further damage so best to just let it sit for as long as possible.

It is highly likely though that it isn't even cement at all, it could be some kind of external render or coating or even a paint or treatment that got spilled. If you know roughly where you picked it up it might help if you can identify any building work going on in the area and see what kind of stuff they are using.


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## Gav147

DLGWRX02 said:


> Do you have a builders merchants, you may be able to get something there to dissolve cement. I know my father in law uses something on his tools (hes a builder) to dissolve dried on cement. No promises it won't cause any reaction to paint but if your careful with application, it has to be better than leaving it on.


That is brick acid and from a merchants will be the full strength stuff, basically it is just Hydrochloric Acid with a few other chemicals mixed in, yes it dissolves cement very well, along with lots of other things too lol, so I would be extremely careful if you do try it.


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## steelghost

If you have a dropper you can try putting a single drop of the full strength acid directly onto the cement. If it is cement, or some other lime / calcium based product, it should fizz a little. If so you probably want to try soaking a test patch of the mark with a 10% dilution of the brick acid, then ideally pressure wash off the acid, and hope that the cement comes off with it.

If there's no fizz it's likely it's not cement and would need something else to clean it off.


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## Dummer

I use jif last time...then follow up with polish because Jif is like 1000 grit sand paper


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