
plating, anodizing, & finishing Q&As since 1989
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Standards for crosshatch loss for aluminum boats
October 20, 2008
I am a QA inspector in the aluminum boat industry, and I am wanting to know what is the rule of thumb for pass/fail on crosshatch testing? (example; there are 24 squares, how many squares lost justifies pass/fail)
Julie SchlippQA inspector - Lebanon, Missouri
October 23, 2008
There are two articles worthy of your evaluation.
www.decorativeresins.com/StrengthOfPaintReport.pdf
The second I think is more informative as it shows images of results after removing the tape and allocates an agreed code to the resultant damage.
www.proinexinstruments.com/technicky_list/Cross_Hatch_Test.pdf
However, the interpretation of the cross hatch test totally depends upon the expertise of the person carrying out the tests.
There appears to be no general set standard for what is classed as a pass or failure.
The ASTM D3359
[affil. link]
is only a method, it is then up to the client to specify at what level/percentage of squares removed they will accept before the coating is classed as a failure. Alternatively, produce your own spec from data you have collected.
Birmingham, United Kingdom
