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MEK and paint cure testing

August 30, 2008

I need to know how many times must I put MEK / methyl ethyl ketone on the painted parts for the cure test?

I have a paint line with 5 stages, actually my set point is 400 °F in the cure oven during 15 minutes, the thickes's part is 1.6-2.0, azko nobel is my powder supplier

Martin Serrano
Engineer - Nogales, Sonora, Mexico

As it appears this is not a customer requirement but a possible in-house test method, therefore, you can determine the number of rubs yourself. First, sort out an item already powder coated that you feel is acceptable for cure by yourself and your clients. Using a Q-tip [affil links] damped/wet in MEK and rub 10 times (back and forth) - stop - scratch with finger nail. If OK, next time rub 20 times. Continue until film becomes damaged. Take this number of rubs, less 10 as your standard test. Re-evaluate, if OK here is your standard.

Terry Hickling
Birmingham, United Kingdom
September 8, 2008

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I perform the test is the following way. Twelve ply cheese cloth, (medical gauze) fitted on the end of a 3/4 inch rod that is part of a jig imparting a weight of 1.5 kilograms. For a thermoset coating, 200 double rubs is full cure, 100 rubs is a good enough cure for most coatings, and 50 rubs you can get away with.

Ron Zeeman
Coil Coating - Brampton, ON, Canada
September 12, 2008