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prpl
06-29-2014, 09:10 AM
I've been lurking a while; finally have a reason to start a thread.

Two weeks ago someone mixed concrete beside my car and covered it in dust. That afternoon it rained and dried so I had no chance to deal with it before the damage was done. The car had a coat of WG DGPS on it at the time. I washed the car and it was covered in water spots that would not come off. I assumed the concrete had etched the clear coat.

I chose 2 test spots. Clay did nothing to help. Optimum Finish Polish on a white pad didn't work either. I ended up using FG400 on a yellow pad and after 2 passes the damage was 98% gone.

Finally this weekend (which is 2 weeks and several thunderstorms later) I cleared time to do a full correction on the damaged surfaces. I started by washing the car.

All of the concrete spots are gone except on the test spots where it looks like I never touched it at all.

I have no honest idea what has happened to my paint. I'm assuming I can just tackle the remaining spots with the DA, but are the other spots gone? If I polish it will they return like in the test sections? Irrational, I know, but I can't believe the only spots left are where I polished them out.

Any thoughts would be much appreciated.

thanks,
P.

Just02896
06-29-2014, 09:17 AM
I've used speedy clean concrete remover and it has worked wonderfully. It's a non acid concrete dissolver and I believe it can be found at Home Depot, lowes, or any masonry supply store.

Speedy-Clean Concrete Dissolver | Non-Acid and Biodegradable Alternative that dissolves concrete! (http://www.speedycleanusa.com/concretedissolverinfo.php)

prpl
07-05-2014, 07:12 PM
When I washed the car (dark red A5) and looked carefully, all the spots were still there.

I hit home depot and picked up some concrete dissolver. Unfortunately it didn't make a difference to the spots. At least it confirmed that the clear coat was damaged and there was no residual concrete.

So I just worked a section or two with the DA then pulled the car into the sunlight to see if i was satisfied. Many sections had to be touched up. It was mainly the horizontal areas so at least I wasn't working the entire vehicle.

Spots are gone.

PiPUK
07-06-2014, 04:33 AM
I've used speedy clean concrete remover and it has worked wonderfully. It's a non acid concrete dissolver and I believe it can be found at Home Depot, lowes, or any masonry supply store.

Speedy-Clean Concrete Dissolver | Non-Acid and Biodegradable Alternative that dissolves concrete! (http://www.speedycleanusa.com/concretedissolverinfo.php)

Sorry but those guys are not being honest. When they say it is 'Non Acid' they (quote) mean that it:

Contains no muriatic, sulphuric, or phosphoric acid

If you care to check the MSDS, it actually is a high concentration of glycolic acid with a pH of 1.5-2. So I am sorry, it may be one of the less aggressive acids but this products is absolutely and definitely NOT non acid.

It annoys me when companies mislead consumers but this has to be one of the most blatant examples.

Setec Astronomy
07-06-2014, 06:36 AM
So I am sorry, it may be one of the less aggressive acids but this products is absolutely and definitely NOT non acid.

It annoys me when companies mislead consumers but this has to be one of the most blatant examples.

If I'm not mistaken there is or was someone marketing a wheel cleaner as "non-acid" because it had ammonium bifluoride in it rather than HF...that one takes the cake.

StuDLei
07-07-2014, 03:01 AM
Glad to read you were able to get rid of the spots.

BillE
07-07-2014, 07:14 AM
Sorry but those guys are not being honest. When they say it is 'Non Acid' they (quote) mean that it:

Contains no muriatic, sulphuric, or phosphoric acid

If you care to check the MSDS, it actually is a high concentration of glycolic acid with a pH of 1.5-2. So I am sorry, it may be one of the less aggressive acids but this products is absolutely and definitely NOT non acid.

It annoys me when companies mislead consumers but this has to be one of the most blatant examples.

:wow:

I think 'mislead' may be a bit of an understatement!

Reading those MSDS sheets is becoming a way of life lately; out of necessity!

Thanx for bring this of (again).

Bill