corrosion ? around light fixture?

[Lily&Me]

Discovered this today.

Can anyone tell us just what it is and how to fix and treat it?

Thanks.

Maggie

[HHaase]

What's the material of the fixture? Stainless or Aluminum?

If it's stainless, that does look like galvanic corrosion. Should clean off with just a scotchbrite pad, but you'll need to put some kind of gasketting between the two if you don't want it to come back.

-Hans

[Al - K4GLU]

http://www.airforums.com/forums/f142...ml#post1122759

[Lily&Me]

Originally Posted by HHaase

What's the material of the fixture? Stainless or Aluminum?

If it's stainless, that does look like galvanic corrosion. Should clean off with just a scotchbrite pad, but you'll need to put some kind of gasketting between the two if you don't want it to come back.

-Hans

I think it's stainless. It's on the ceiling of the Interstate, which with the walls all appear to be stainless.

From reading the thread link Al-K4GLU posted, looks like we should treat with WD40, scrub clean and maybe apply a clear coat of some sort before adding a gasket. The corrosion had just started to creep out from under the fixture, which is why we noticed it.

If it's aluminum, should we do something different?

Thanks, all.


Maggie

[ROBERT CROSS]

Maggie,

Is there any evidence of a water leak there?

I believe both the fixture and ceiling are aluminum and you have a bit of the infamous filiform
.
Try to get the fixture out as far as possible.

Spray the area of corrosion with wd40 and let it soak in, wipe down with a microfiber cloth. Repeat several times. Take/post another pic so we can see how much has come off. That will help in determining the best way to seal the area.

It looks as though it's extending past the bezel just a little, so it shouldn't be very obvious once it's sealed.

Bob

[Lily&Me]

I haven't seen evidence of a water leak, but this is near the Fantastic vent that leaked horrifically the first year or so, so that may well have occurred.

We are doing the WD40, some of this stuff seemed rather thick and came off in small sheets, like a scab.

Be back with a picture.


Maggie

[Lily&Me]

This seems to be cleaned down to a rough, rather corroded surface. Should we sand this with something?

BTW, did take a look at that other thread on filiform corrosion. Wondering if it matters that this is inside our unit.

Did find a couple of other small spots within this same fixture, also treated and wiped.

[ROBERT CROSS]

Originally Posted by doug&maggie

This seems to be cleaned down to a rough, rather corroded surface. Should we sand this with something?

Did find a couple of other small spots within this same fixture, also treated and wiped.

Maggie,

I would wipe down the area with mineral spirits and tape around it with blue painters tape to keep from marking the undamaged area.
Then use a scotchbrite scrubbie with more 40 to see if you can get more of it off. The last operation may be 40 with superfine grit wet/dry sandpaper, but try the scrubbie first.

Bob

[TBRich]

It sure looks like filiform..."growing" from the raw-cut edge of the aluminum interior skin...just how it appears on the outside of some newer rigs... It's odd to be occurring on the inside ... and to me it indicate that there is/was a leak somewhere that's allowing the are to become moist. I'd treat it with Corrosion-X and Boeshield T-9. It's not likely to remove it, but it will stop it.

[Lily&Me]

Okay.

We are at Edisto Beach and used borrowed WD40 because ours had dried up.

We will be leaving here Friday morning, will pick up mineral spirits et al and follow the rest of these suggestions. We have clear coat at home and will be there by the end of next week.

Back in a couple of days with a new picture.

Thanks,


Maggie

[Lily&Me]

We have cleaned with mineral spirits and scrubbed with WD40 and Scotchbrite, repeated X2. This is what it looks like at this point. There is one deep spot on the largest area of corrosion. Do we need to use fine sandpaper, as well? One of the holding brackets was rusted and broke, and the entire cut surface for the fixture appears corroded and was treated.

[JFScheck]

Disimular metal corrosion could be the cause, especially if your Airstream is subject to high humidity.

Have you treated it yet? If so - how?

[ROBERT CROSS]

Doug,

It's really hard to tell from the pic how deep the corrosion is, I've found it best to remove it completely down to the skin. But that's been on exterior panels using a dental scaling tool. From a distance, hard to notice.

But inside, where distance is limited.....
If it were me I would clean the hidden areas further and clear. Wire tooth-brush or fine emery. Then get the smaller visible area as smooth as possible and seal/clear.
The more you disturb the surface the more visible it will become.

Keep a close eye out for further progression, and save any more aggressive action for later if needed. Stainless paint is an option, but not a "perfect" match.

Wish I could be more help.

Bob

[tpi]

It looks like corrosion brought on by a leak, or at least chronic wetness. It sounds like you have possibly found and repaired the leak.

If it were mine, I'd look for a way to put a gasket between the stainless and the aluminum if possible. I'd also get some ACF 50 and treat the aluminum. Then I'd check it occasionally especially after a rain or humid conditions to see if it is getting wet. Plus reapply the ACF 50 occasionally. Probably WD40 has some ability to inhibit corrosion and you could use that instead as long as you monitor it, and insure it isn't getting worse. Treat not just the corroded area, but all around the round cut.

[Lily&Me]

Thanks, guys.

Just where would one find a dental scaling tool?

Seems like that would be the most precise way to scrape some more, followed by sanding before sealing with clearcoat.


Maggie

[ROBERT CROSS]

Originally Posted by doug&maggie

Thanks, guys.

Just where would one find a dental scaling tool?

Seems like that would be the most precise way to scrape some more, followed by sanding before sealing with clearcoat.


Maggie

PetSmart....Amazon

Bob

[Lily&Me]

Originally Posted by ROBERT CROSS

PetSmart....Amazon

Bob

Aaah, we have to go there when we get home, anyway.

Can we replace the little clippie thing that broke, do you think, or have to get a whole new light---from the Airstream factory?

Thanks,


Maggie

[ROBERT CROSS]

Originally Posted by doug&maggie

Aaah, we have to go there when we get home, anyway.

Can we replace the little clippie thing that broke, do you think, or have to get a whole new light---from the Airstream factory?

Thanks,


Maggie

Maggie,

Take the fixture to Home Depot they may have something you could adapt.

If not maybe a couple small pieces of double sided tape.....that would also act as a gasket. Get the thinest possible to make it less noticeable.

Bob

[Lily&Me]

Originally Posted by ROBERT CROSS

Maggie,

Take the fixture to Home Depot they may have something you could adapt.

If not maybe a couple small pieces of double sided tape.....that would also act as a gasket. Get the thinest possible to make it less noticeable.

Bob

We right now have rope caulk and masking tape holding it in place, and the rope caulk might serve as a pliable gasket around the opening when we get to that point.

We inspected the light just opposite this affected one, and there is a small amount of corrosion there which we will also tend to.

My fear is that corrosion is working its' way through the ceiling of the interior, from the leaks caused by the install issues with the original vent fan, and that eventually we're going to have to replace a chunk of the ceiling.

Don't know how we could even get to it to examine it, wonder if it is worth taking it to our body shop to do something to access this.


Maggie

[ROBERT CROSS]

Maggie,

Our front ventfan also leaked from poor install. The plastic cover had cracked at the hinge mount holes, hidden by copious amounts of caulk. Fantastic vent warranted the cover even though it wasn't there fault and it was 5yrs old at the time, great CS!!
If your comfortable getting up on the roof it's pretty easy to check.
Just stay off the end caps and walk carefully along the rivet lines...in sneakers.
At home I use an A-frame ladder along the side at the curbside rear using the awning cover for support. At the campsite we have a telescoping ladder that I use at the same area leaning on the rear window rain gutter, top of the ladder covered with a terry fender cover to protect the trailer just in case. Helper holding the ladders at ALL times!!

Is it the interior ceiling that you feel needs replacing?

Bob