Using POR-15 without dropping the Belly???

[crabbey1]

1976 Argosy 22' - I am in the process of replacing the sub-floor with the Shell-on/Belly-on. Am I wasting my time with the POR-15 if I can't paint it on underneath the frame members? Without taking the belly off, I can only reach where the paint brush reaches... Also, the POR-15 won't have any negative effects if it gets on the interior aluminum panels, will it? Any opinions are welcome. Thanks!

[perryg114]

It won't hurt the aluminum. It will stick to it pretty well. I would paint anything that is rusted and that you don't want to rust. If you don't have leaks and wet fiberglass insulation you have eliminated a lot of your problems. The problem that you will have is that it will do a great job of glueing the belly to the frame rails. Your frame looks pretty good. If you are this far into it, I would putt the belly skins and do it right. Not easy to insulate from the top unless you do it like Airstream did by putting it between the frame and floor.

Perry

[crabbey1]

I planned on just painting the POR-15 on as best I can to the frame and then laying in the 3 1/2 pink insulation into the gaps like in the photos... Is there a better way? I am just following what AS did originally.

[perryg114]

Is that the original insulation? Why did you even take the floor out? It does not even look like it has been wet. Airstream usually puts a mat of fiberglass over the frame and puts the floor on top. If your trailer will ever see a wet environment for long the fiberglass will get soaked with water and it stays wet and rots the frame. Since you are in California you have been lucky and your trailer shows what an east coast trailer would look like in 5 years. You trailer would just be a shell holding a rusted frame together if it were in this part of the country. If it stays in California just put the floor back in and don't bother insulating it or painting for that matter. How you going to get the floor back under the C-channel?

Perry

[HiHoAgRV]

I'd say any level of rust prevention is better than none. I am wondering how you are gonna bolt everything together with the belly pan installed.

[pinkflamingoes]

I am putting in my 2 cents worth here and adding the likelihood of mice and other critters loving that insulation as nests. I know the advice here is all pointing to a belly-pan off, but you can do so much more if you do remove the belly pan. Replace the insulation with Prodex or some other kind, see and repair the frame if needed, paint the whole frame, etc.

[Tony S]

I understand the reluctance not to go deeper than you have to. I too felt that way and am in the middle of a shell on belly pan off renovation. I didn't want to loose control of the job with my lack of experience. But what I have found is when people tell you it would be easier to .... and it is leading to going deeper on the one hand they are very right. I wouldn't worry too much about taking the belly pan off.

I used Por 15 on mine and loved it. I followed the direction and it worked out. I also sanded up the paint on the the first section of my trailer, still in the A frame, and painted it as a test if nothing else, and it stuck real nice. It won't encapsulate the rust in the same way but did stick well. As the Por drips down on the belly pan it will puddle and really attach the aluminum where it does.

Don't get it on you.

Good luck

Tony

[crabbey1]

Originally Posted by perryg114

Is that the original insulation? Why did you even take the floor out? It does not even look like it has been wet. Airstream usually puts a mat of fiberglass over the frame and puts the floor on top. If your trailer will ever see a wet environment for long the fiberglass will get soaked with water and it stays wet and rots the frame. Since you are in California you have been lucky and your trailer shows what an east coast trailer would look like in 5 years. You trailer would just be a shell holding a rusted frame together if it were in this part of the country. If it stays in California just put the floor back in and don't bother insulating it or painting for that matter. How you going to get the floor back under the C-channel?

Perry

Hey Perry. That is not the original insulation. That is brand new insulation and a slightly wire brushed frame waiting to be be POR-15ed.

There was some water damage right at the front where the Fresh water tank sits and fills. There was a leak.

I have already tested the new sub floor and it is easy to slide right into the C-Channel. I had to cut it into 3 sections. They will all be screwed back into the frame with the E-Bolt style screws that Vintage Trailer Supply sells.

[perryg114]

If you are not going to remove the skins then leave the insulation out. You live in a mild climate and won't notice it being gone. That pink stuff is evil. I hate working with it even in houses. It might be possible to support solid foam insulation on some sort of ledge that is attached to the frame rails. Usually you glue it or screw it to the bottom of the subfloor. You can always remove the skins later (assuming they are not glued to the frame with POR 15) and add insulation. I attached my center bottom skins with screws for easy removal. You can also section the skin so you can take it off a little at a time. It you paint bottom of the floor and frame and seal everything you can even get by without skins for a time. Where you are probably forwever. You can do things in stages as you get time.

Perry

[Lumatic]

Originally Posted by perryg114

It might be possible to support solid foam insulation on some sort of ledge that is attached to the frame rails.Perry

What was recommended at the Vintage Trailer Academy was styrofoam glued in with aerosol foam around the edges. no ledges needed

[goshawks00]

What type of foamboard? Maybe 1" foil backed?

[perryg114]

You still have to be able to get to the back side of the foam. I would assume you put a bead of foam in a can under the bottom edge of the insulation.

I used 1/2 RMAX with the foil on both sides. I used 2 layers of this. You can use standard construction adhesive with this because of the foil. The foil also acts as a radiation barrier. Use whatever you can find locally. It varies by location. 1" of foam board is as good or better than 1.5 inches of fiberglass.

Perry

Originally Posted by Lumatic

What was recommended at the Vintage Trailer Academy was styrofoam glued in with aerosol foam around the edges. no ledges needed

[desertair27]

It looks like you laid the insulation on top of the belly pan filling up that whole empty void,is that right? I think if you have the insulation in contact with the belly pan you will have serious problems with the insulation soaking up any water that finds its way into the belly pan area when driving in rain and just under normal rainy conditions.
Mike

[crabbey1]

Originally Posted by Lumatic

What was recommended at the Vintage Trailer Academy was styrofoam glued in with aerosol foam around the edges. no ledges needed

Did they install it from the top down or did hey drop the belly and install it from underneath?

I have rethought the pink stuff... It does go from pan to floor and will soak up moisture. I would love to use Foam Insulation but couldn't think of a way to install it from the top...

Perry -

I agree that I can do the underside at a later time. That is what I have in the back of my mind now anyway. I really just want to get this floor situated so I can start rebuilding the interior and use the damn thing...

Later on after the inside is back to norm, I can tackle the belly. Drop it, paint the remainder of the frame and maybe add new insulation.

[perryg114]

Well paint the top of the frame rails carefully so you don't glue the skins on. The rest you can get to from underneath but it is a messy job and POR15 WILL NOT COME OFF your skin unless you use a belt sander. It has to wear off.

Perry

[Lumatic]

Originally Posted by goshawks00

What type of foamboard? Maybe 1" foil backed?

I have not done this myself, but I would use 2" blue or pink styrofoam. It is a closed cell foam so a moisture barrier is moot. There may be something to be said for a refective barrier, in which case I would add Reflectix.

[HiHoAgRV]

Originally Posted by crabbey1

... They will all be screwed back into the frame with the E-Bolt style screws that Vintage Trailer Supply sells.

What are you going to do in order to bolt thru the C channel, the floor and the out riggers? IMHO, the bolts that go through all 3 are probably the most important fasteners in the construction of an Airstream, otherwise the only thing holding on the shell are a bunch of wood screws right at the edge of the floor...

I cant see a method to do this with the belly pan still in place.

I've seen folks start down this path but never seen the final outcome.

[crabbey1]

What a rough weekend. My body feels wrecked. I also found a new friend (see first photo)...

Well, here is my final choices for the floor. I used a combination of a hand wire brush and a drill wire bit to remove all the rust. Then I painted with Rust Destroyer. I was local and supposedly eco friendly. Next, I measured and cut the 2" Foam Insulation with Foil. Most of them fit very tightly. I filled all edges and voids with cans of Insulation Spray Foam. Finally, I brought in ACX plywood that had 2 layers of Penetrating Polyurethane applied. I used the screws from Vintage Trailer Supply. I pre-drilled holes and tapped the frame so they screw right in and tighten everything together.

I completed the first section on Sunday and I am currently on the 3rd section. I will update when fully complete.

[pinkflamingoes]

That looks pretty dang good.

[Thisisliving]

I took all the pick stuff out. There’s not enough there to make any difference. It make a better mouse house than anything else. P.O.R. all the places you can reach. Unless your going to live in it full time in the great north, you should be o.k. Just FYI