The Stovebolt Site Forums The Shop Area Paint and Body Shop No rear access, patches

That's probably a huge discussion I don't want to start. There is no moisture where I live. We never think about rain, humidity or salt here. That's why everybody buys vehicles from AZ and CA. Not much rust. "Trapping moisture" can be defined by different people in different ways. I really don't know the science behind or the different definitions of "trapping moisture".

As far as in general though, liquid water from leaks is one issue. Standing water is not good. Condensation is another source of water. Condensation can form anywhere. Most areas that can accumulate liquid water have a drain method built in. Drain holes. Condensation has to evaporate by breathing and by heat. Metal does not absorb water. So the water forms on the surface and starts to rust if it does not evaporate. I equate my particular backing pieces to the many pinch welds there are on my truck. The tailgate inside can breath and drain due to holes and openings. I don't really have a definite answer as to what will happen in time. I know as far as in AZ, it will not rust more than oxidize slightly. The truck came from Grass Valley, Ca. It has very little rust. It is 58 years old.