Should I replace this panel?

[mblaize]

There are some spots of aluminum oxidation on the inside of my baby. I have read that it's from two different metals touching for sometime- but as you can see, it's all aluminum in some areas.

The worst oxidation is in the back where my c channel has a steel L piece connected for years.
I am replacing the c channel but it doesn't have much to rivet to! Replace the whole panel or patch? Also any advise on the interior corrosion repair would be much appreciated! I'd rather not remove the panels to sandblast by the way

[mblaize]

Here is the interior...

[J. Morgan]

I would put a nice looking patch on it, but I am a practical kind of guy.

The panel looks great except for the bottom.

Gradiens super tenui glacie.

[sgschwend]

It looks to me that you need to stop the reason for this corrosion.

I don't know but perhaps it is from "galvanic" chemistry. In the marine environment they install a galvanic isolator; to protect the metal in the boat. Metal being susceptible to small voltages in the shore power cord ground lead.

The protector is two diodes in series with two other diodes in the opposite direction in series. They blocks any current flow in the ground lead of voltages less that 1 volt or so. I noticed on my trailer quite a bit of stay AC voltage and was wonder what is going on, given I have attached the power breaker panel ground to the trailer frame. It is almost like the receptacle I am plugged into is messed up, but tests show it OK. I am in renovation right now so it is on my list of things to do.

You can measure the ground voltage by measure between the nearby ground (some metal part connect to the soil) and the trailer frame with your AC voltmeter. If you don't have anything just hammer is a rod of some kind into the ground. It should be zero volts, mine is high enough I can feel it (such as the inside of my forearm).

[fwjumper]

Depending on how nice the rest of your trailer is, I would probably remove and replace it. Remove it, clean everything very well, make sure that there is no steel touching it (or near it, to the extent possible) Isolate it with sealing tape available from vintage sources etc. and rivet into place. It is a flat panel which helps a bunch. If you want to "patch" it, which is a reasonable option (not much less work if you do a good job), I would cut a section off, thereby removing the malignant material, and attach the patch a the rivet line just below the tag. As previously said, whether I would patch or not would depend on the overall condition. If it's a nice trailer, I wouldn't even consider it. I'm guessing it's a nice one.

[kdickinson]

Agree with fwjumper - replace now instead of wishing you had later

[J. Morgan]

You could go to the trouble of replacing the panel, but then a one or one and a half inch tall patch would fix the issue and only you and Airstream purists would ever know that you used a patch, and half those who know would be cool with the practical solution.

If it was my trailer I would patch. The panel itself is 98% good, and hey, they patch the crap out of airplanes.

#JustSayin...


Gradiens super tenui glacie.

[Streamracer]

How wide is the gap? Would a piece of trim molding with the plastic insert not cover it?

[HiJoeSilver]

I know about the exact spot you're working on. It looks like you have the interior skins off in that are so you'll have easy access now, not later. So there are some options.
There is a trim piece that goes around the back at that level. Does it cover the corroded aluminum. If it does you could cut a piece of aluminum that will be as wide as the area that will extend a few inches above and below where the corrosion is. Then you could slip it up behind the panel and rivet a nice horizontal row holding it in place above the corrosion tying it to the panel, then put a strip of roofing felt paper between the aluminum and steel to stop the contact. Then rivet the aluminum back on bottom to the c channel to seal up the bottom again. The few inches that extend down past the bottom of the floor can be bent forward(before or after installing) forming a flashing to block the water problems back there.
Another option, is replace the panel. It's a pretty straight forward piece to replace if you use the old one as a template and can cut or have a piece cut to match with nice clean cuts. While you have the panel out of there you'll be able to get that steel angle out of there and replace it. I took my steel angle out while doing a full monte. Topknot to a metal shop and told them to make a duplicate of the steel one in aluminum, no more rust, rot, or galvanic problems. It's more than strong enough for the application back there. You can put the new angle in, put the new panel back on and be good to go.
Mine wasn't as corroded but the wood floor there was basically rotten away, and the steel angle just about corroded away in many places. So I didn't have to replace it, and ended up using a combination of the two aboveboard to replace, repair, flash, and seal the area from future moisture damage.

It looks like you have good access back there, not sure about from underneath in the front, but if you have access to the 4 corner hold down bolts(they're the bigger ones) that go through c channel and the frame they have rectangular steel plates as washers on top that are probably very corroded, those can be replaced with aluminum as well.

Just a few ides from my experiences.

[mblaize]

The banana peel would definitely cover the area but I want to replace the c channel in this area- and there isn't much left to rivet it to.

I haven't seen this yet on the forum, but I am going to take out the c channel and that wretched but of rusted steel that caused this problem and replace it with the double c channel I bought online. It only came in a 16 ft measurement so might as well

[Aerowood]

I replaced the rear skin. I also replaced the steel angle with .063 2024-T3. I made it wider to attach to the two vertical frames that are on each side of the window.