Ask the Expert Question-and-Answer Archive

by Ron Joseph

May, 2007

Laboratory Testing of MIL SPEC Paints and Coatings

Q: We have a requirement for a military customer to paint their parts, since we don't have any experience with painting we are working very closely with a local paint shop to develop them meeting military standard for painting.

The standard they are asking for are:

Paint by    Mil-PRF-22750

Primer by   Mil PRF 23377 Type 1 Class C Yellow (steel parts)  &  MIL P 11414 (aluminum parts)

Pretreating     TT C 490 (steel parts)  &  MIL C 5541 (aluminum parts)

Cleaning    TT C 490

My question is:

1. Since we are helping to develop this process we were wondering what tests are required to be performed in order for them to be able to comply with the Mil-Std?

Most of the standards have a list of tests they need to comply with, but maybe not all of them are "normally" required

Specially, Mil PRF 22750 is asking for tests on the paint itself and also in the process, since the paint that we bought has a statement in the certificate of compliance that comply with many of those tests we would like to know if that is enough or tests againg need to be performed?

What kind of tests are "normally" required to be performed in a lab and which ones doesn't?

Also, Do you know who can make those tests?  We are in Mexico side (just in the border with California) so we normally use vendor near the LA area.

A:  When you purchase mil-spec paint that has been qualified by the military you do not need to conduct any tests yourself provided that the coating appears on a Qualified Products List (QPL).  Therefore, with regard to MIL-RPF-22750 you need to determine what company is already on the QPL and provided you purchase an approved coating you do not need to perform any further tests.

With regard to specifications such as TT-C-490 and MIL-C-5541 that cover pretreatment processes, you might be required to conduct tests to ensure that the pre-treatment process complies with the respective specification.  The most important tests under these specifications deal with corrosion resistance and in the case of MIL-C-5541 also the coating weight (mg/ft²).

If you would like some testing to be done I might be able to assist you.

Regards,

Ron Joseph