I see a lot of resto shows where they media blast the frame, or chemically strip it. Then, the usual route is to powder coat it. But I wonder what happens to the insides of the boxed in frames. It would seem to be difficult to get a good coating on it. If you get the outside super well protected, what happens if the insides of the rails are bare metal?
I also don't see much attention being paid to the seams between riveted and bolted flat sections. Just painting the outside won't work for long, as moisture will be wicked up between the surfaces via capillary action. The only solutions are to separate the parts, coat them, then reassemble. Or (less effective) try to run a bead of sealant around the edges.
My '89 truck has been sitting outside for 10 years, with no rust. None. The factory has done a great job with improving corrosion resistance. Are they galvanizing the frames at the factory now? And has anyone considered galvanizing the frame during a resto? That would cover the inside inaccessible areas, too.
