Rust Rot in the Rear Frame Bumper Area

[HamiBambi]

First of all is Aluminitus totally terminal or might I one day be cured?

Some of you may be familiar with the fact that I'm doing a shell off restoration of my 1962 Bambi. Well, since I figured out that this is going to be a looong process and I want to hit the road and do some rallying and meet some of you good folks face to face, I've now aquired a second vintage airstream that "doesn't need any work". Which is to say that it's totally intact and original, appears to be in really good condition, was obviously well cared for, and as far as I can tell has NO FLOOR ROT. Which was what I found my Bambi suffered from in spades despite all the other criteria being fairly robust.

There is however one thing I've noticed in my "new" 1960 22' Safari. The rear frame members are quite rusty where they emerge from the belly pan in the rear. I also have noted that several interior rivets around the curved endcap in the rear of the trailer are broken or missing which leads me to believe there is some flexing going on in the rear of the trailer. Every exterior rivet is intact, there is no noticeable sag behind the axle, and as I said I find absolutely no evidence anywhere in the interior of the trailer of floor rot or leaks.

I therefore have two questions.

1. Based on what I've described does it sound like the frame rot is isolated to the very rear portion of the frame. And is this somewhat common given that these members are exposed to the elements and not protected by the belly pan?

2. Is it possible to repair and strengthen rear frame members whithout taking the shell off. ie. Can one simply open the belly in the rear and weld in new frame steel as needed without affecting the rest of the trailer or is this a pipe dream?

As I said the exterior rivets are all good and all the interior rivets are good except for the ones along that one seam of the upper edge of the rear interior end cap.

One additional question. My belly pan on the Bambi wraps around the interior C channel making it impossible to pull away without removing the shell. Is it possible (and I assume this has been covered somewhere in the forums so perhaps you can direct me to the thread) to drop just a section of the belly pan to do the needed frame work behind the wheels? Maybe just by cutting it away and then reriveting or something?

Thanks again all. Pictures of the new Safari to come soon!

Steve H.