WATER BREAK TESTING

Q. We have some folks we work with who discredit the water break test. I have personal experience with painting and plating where the water break test is very important. We currently have some hardware that is failing the water break test, and the paint processor is saying the water break is not a test they ever perform. They say we are unique in this. I have worked for a couple other companies and we always used this test. I have never heard of a painter not using a water break test to verify cleanliness prior to painting. The substrate that we are painting is chemical conversion coated 6061 aluminum alloy.

Can you please help identify some useful sources and argumenets either for or against water break testing? Thank you. D.B.

 

A. It is so simple and non-destructive, I can’t imagine anyone discrediting the water break test for surface cleanliness prior to painting. It has been used throughout the manufacturing industry in the painting and plating areas for years.

How does your processor check his surface pretreatment? I guess he can do adhesion tests, which are destructive, on painted samples rather than on parts. If so, the water break test would save him man-hours, which equates to time and money.

After searching my vast archives, I couldn’t find good references to water break tests, so I can’t quote you “Chapter and Verse” for or against it. Water break testing is not in the ASTM Annual Standards Sections 27, 28 & 29, which are paint related, but neither are other cleanliness tests. It may be in the ASTM Sections covering electroplating, which I don’t have. However, I am sure you can get backup information for your case from pretreatment chemical suppliers and paint suppliers.