# Very cool cross section of layers of paint



## OraarO (Oct 19, 2007)

This is from a job I did last year that is having some issues. The products I used did what they were supposed to, but there is a problem starting in the bottom layer (maroon).

Anyway, I thought this image and measured mil. thicknesses would be interesting to some...


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## nEighter (Nov 14, 2008)

wow that is cool. Tell more. more pics too.


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## OraarO (Oct 19, 2007)

This is from a roof that was painted last summer. Sorry, it's only half of the picture, but when I try to copy it from an .pdf file, it will only grab one half at a time. If anyone knows how to grab a whole picture from a pdf, please let me know! 

There is the original "baked-on" finish that is not shown in the picture. The picture shows the next layer applied, a maroon coating in the bottom, middle of the photo. The second layer is a kind of elastomeric "orange" coating.
The third layer is a white primer/bonding coat I applied. Then two coats of a really thick, high-performance elastomeric coating (gray). The topcoat is an acrylic "purple" for the final color.

The reason I have the pictures is that there are some areas that have failed, and the company that sold the product is investigating why it happened.


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## acmasterpainter (May 15, 2011)

Good luck with your issue.

This guy, patrick Baty is a world leading expert on how to analyse paint. http://patrickbaty.co.uk/paint-analysis/cross-sections/ The average room has 40 to 100 samples taken where he has to analyse the layers to determine the original colours on historic buildings.

He once had a client who accused him of selling sub standard paint and he did an analysis to show that the black marks on the painted cills were not due to failing paint. The streaks were actually rain water bearing particles from the trees in the park opposite, and fuel-based pollutants from traffic passing by the property. Cant argue with science sometimes.


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## OraarO (Oct 19, 2007)

On this job, the coating the manuf. recommended are working correctly, but the first layer of paint applied (after the baked-on powder coat) is likely the cause of failure.

The pictures show that I applied the product at the correct dry film thickness, and the adhesion tests had zero issues, but in some areas that original coat likely let loose, while the coatings on top of it are elastomeric and are performing correctly, the inflexibility of the initial coat is causing all the layers (including mine, a total of 9 in some areas!!!) to fail.


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