To prime or not to prime. That is the question.

Bare aluminum alloy will corrode if left uncovered without something to protect it. The aluminum skins used on RV aircraft are all 2024-T3 alloy. They are “alclad”, meaning that both sides of the sheet are coated at the mill with pure aluminum. This forms aluminum oxide, a corrosion resistant material which need not be primed or painted for adequate service as an airframe material. However, if the airplane is to be kept in a salt-air environment, or if a greater margin of corrosion protection is desired, priming the entire inside of the airframe is a good idea. Remember that priming will add cost, weight and time to your project. – Van’s Aircraft, Section 5.1

With Florida known for its heat and humidity, we’ve decided to prime. Although Zinc Chromate was the standard for many years, 2-part epoxy primers have come along that are better and more durable. We’re using AkzoNobel 463-12-8. This stuff is extremely carcinogenic!

A good quality respirator in a well ventilated area is a must.

We made a paint tent out of PVC in the garage and got set up.

The primer has an 8 hr pot time but dries to the touch in about 5 minutes enabling me to spray both sides in short order. When fully cured, this stuff is extremely durable!