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CROSS HATCH ADHESION TEST

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I would like to thank those who answered my request for a "consensus" on how long after the last coat is applied, and the time when a "Cross Hatch Adhesion Test" is done.

I was writting an article on this test, and after doing much research with coating manufactures, companies that make the "CHAT" test kits for doing this test, a few chemists, and also checking with ASTM and ISO.

There was no consenus, there were too many different answers, no standard to really use in my article.

I would like to share what I consider one man's opinon, and what I wrote in my article concerning the test.

"Because of the numerous coatings, and methods of applications, and different systems for drying on the market today, I cannot give a definitive answer as to when to do this test on the coatings you are using, I personally prefer doing the test after a week to ten days, and then doing another test two weeks later to double check any differences, always keeping notes on the two samples to make comparisons for future references. This suggestion includes the air and heat dried coatings.

If a faster test must be done, then these calculations could be used, If less then 20% of the coating is removed this is considered passable, if greater then 20% of the coating is removed this is considered poor adhesion between the coatings and substrate.

I hope someone will find this helpful.

Thanks again for your answers. I considered all of them.

Mac Simmons

mac simmons
- Massapequa, New York USA