Belly Pan /Skin Loose

[Old_Town]

Much to my surprise last month the rear portion of the belly skin had come loose and was hanging down about 2-3". Very Disapointing. I re-riveted the skin but it seems to need some midpoint support of some sort. I was thinking a piece of aluminum angle or the like. There is now a noticeable sag caused by the weight of the insulation above.

This happened at the rear of the trailer.

Has anyone here experienced anything like this?

Thanks in advance.

-Ty

[pmclemore]

Oh, yesss. By the time I made it to JC on our way back from AK, our trap door was hanging like Dennis the Menace's bunny suit. But not nearly so cute.

I had tried repairs of my own before we left, but they didn't hold up. No pun intended. The factory did exactly what you proposed - rivet repairs and they used aluminum strips in several strategic locations.

It is going to happen to all Airstreams - and should be a part of regular maintenance to inspect and repair before you get caught out in the open.

Pat

[Old_Town]

Thans for the reply Pat. I will probably install the aluminum angle this weekend. I will post pictures if I do.

Regards,
Ty

[Beginner]

Belly Skins
This is how I repaired mine.
The skin was corroded almost through and the rivets had pulled through. The pan was very loose.
1. I located the center of the frame rib (steel) all the way across the bottom.
2. Took a chalk line and pooped a line across the bottom.
3. Took a small piece of the aluminum strip and made a guage (made a center line down the middle of it. Held the center line on the belly skin and with a pencil marked the front and rear of the strip with a pencil.
4. Layed out and drilled the holes in the patch strip.
5. Had a friend help hold and align the strip between the pencil marks on the belly pan on each side of the rib.
6. Drilled the first holes (into the rib) in the middle and worked out from the middle. This will prevent bunching or puckering that will occur if you start at one side and work all the way from one side to the other. A very sharp 1/8 inch bit is necessary.
worked out from the middle until finished.
See picturers at
http://www.airforums.com/photo...00&userid=7015
and
http://www.airforums.com/photo...00&userid=7015
I did not seal the rivets or the patch because if any water gets on top of the belly pan you want it to seep out. However if the steel rib is showing, place electricians tape on rib to prevent the aluminum patch strip from touching the steel. The reason the aluminum corroded into at the ribs in the first place was due to dissimiliar metal corrosion. The tape prevents the aluminum from touching the steel rib.
I have local supply of the large headed (aluminum pop) rivets here in Norfolk if you are interested.
Good luck.
Beginner

[pmclemore]

Neat job, Beginner. I will likely need to do this on my new-to-me rig this spring.

Pat

[bevman]

I just spent the morning under the flying cloud tacking up the sags in the belly pan. Before I closed anything up, I snaked the hook of a coathanger in the gap. I was not amazed at the rocks and mouse nests that I pulled out, but I WAS amazed at the number of peach pits and similar-sized pieces of gnawed sheetrock. What manner of rodent has a taste for gypsum?

[osolow]

How thick was the strip that you used ?

also how wide was it ?

i have the same problem on my 1990 i was planing on fixing it in some what the same way. but i thought about the useing some kind of sealer between the strips, but the water seepage is a good point.
i would think liquid electrical tape would work good aswell

[Beginner]

osolow
I do not remember. I'll measure today and let you know later today.
Beginner

[yukionna]

Originally Posted by Beginner

...However if the steel rib is showing, place electricians tape on rib to prevent the aluminum patch strip from touching the steel. The reason the aluminum corroded into at the ribs in the first place was due to dissimiliar metal corrosion. The tape prevents the aluminum from touching the steel rib...

Thanks for the detailed instructions! I have a question about the dissimilar corrosion -- if the aluminum rivet is fastened thru the steel, won't corrosion occur at that intersection of dissimilar metals?

[osolow]

thanks beginner i would appreciate it

[Beginner]

osolow
The Strip I used was sheared off a sheet by a local sheet metal company.
It was 8'6'' long, 3'' wide and .038'' thick which corresponds to a guage number. I cut the length to fit.
Yukionna
The pop rivets were still in place when I made this repair.
The skin had corroded away from them.
I can only assume that the pop rivets are made of a near pure grade of aluminum as they corroded much slower than the skin.
Beginner

[musketeer]

Beginner,

Your post has been very helpful as I have the exact same problem on my "89 Excella and I am going to do the same repair. I have the strips sheared and ready but am trying to pick the right rivet. There is a Avdel Avex pulled rivet with an aluminum mandrel and a phospated steel stem, they are used on home built aircraft : Aircraft Construction, Riveted Joints (Part 2 of 2)

This looks like it would work well but is difficult to find. What rivet did you use and where did you buy it?

Thanks a million!

[Beginner]

musketeer
I bought the rivets from American Maintenance Suppliers.
Their phone number is (757) 420-0711.
They are wonderful people to deal with (mom and pop type set up) very customer oriented.
I just bought two bags one of each pop rivet.
I mady my choice by head configuration.
If you like I can go by there and get the same thing I bought and sent them to you.
A bag (of 100 I think) was not that expensive.
Beginner

[musketeer]

I think I can get what I need at Fastenal which is close at hand, but thank you for your very kind offer. My goal is to have my belly skin and propane line reattached and my new water heater working this week. I'm tired of having everything torn up!

Originally Posted by Beginner

musketeer
I bought the rivets from American Maintenance Suppliers.
Their phone number is (757) 420-0711.
They are wonderful people to deal with (mom and pop type set up) very customer oriented.
I just bought two bags one of each pop rivet.
I mady my choice by head configuration.
If you like I can go by there and get the same thing I bought and sent them to you.
A bag (of 100 I think) was not that expensive.
Beginner

[musketeer]

I completed the same belly pan fix as Beginner. I used 4" wide strips of .032. I loosened the skins first and applied Por 15 to the frame, but really didn't find much corrosion. Riveted on the strips. I did use vulkem to seal them as I want to keep road sray away from the frame and I have a few weep holes which will let any moisture inside out. Thanks, Beginner!