Ask the Expert Question-and-Answer Archive

by Ron Joseph

April, 2002

Applying CARC Over MIL-DLT-24441 Epoxy

Q. Can this topcoat be applied over F-150, MIL-DLT-24441 and is there a tacky state requirement like using silicon alkyd over epoxy. I think the primers 23337 and 53022 usually associated with 46168 are epoxy but don't know if they are different from 24441 epoxy-polymides

A. In general you can apply polyurethanes over epoxies, and I would imagine that you can do the same with MIL-C-46168 over MIL-DLT-24441. Always be aware that you should not apply any topcoat to over an epoxy if the latter has already been exposed to sunlight for more than a few hours. (This limitation might differ between coating formulations.) In any case, I would never recommend a new paint scheme unless you have performed experiments to confirm that the system will work.

MIL-P-23377 and MIL-P-53022 are epoxy primers.

Finally, I don't understand your comment "... and is there a tacky state requirement like using silicon alkyd over epoxy." Can you please explain this further?