wood walls in an A/S?

[Dave Cole]

was thinking about replacing the wall paneling in my '69 tradewind. as nice as it is to have it be 'original' the textured white vinyl isn't as classy as a trailer this nice deserves. it may not happen for another few months, but i am thinking of going with a birch or maple interior with aluminum trim, much like vintagevacations.com has done to their spartan, only without the wood floor. figure the ends of the trailer in a light yellow wood would be sexy as hell. if doing the whole thing is too much wood, i might paint some of the center pieces a nice light blue or light green.

Since all the vinyl is intact, i have a full set of teplates already.

(of course, i would save everything i took out for the day when a full resto on a '69 seems like a good thing and leave notes in the walls as to the location of the storage spot)

additional motivation comes from all the mouse poop in the trailer when i got it--might be time to issue some eviction notices and replace the insulation.

so two questions:
what's behind that paneling anyway?

and

anyone out there ever retro-fit wood to a newer A/S?

[airstreamcaravel]

Airstreamphotos.com

http://www.airstreamphotos.com/photo...papass=&sort=1

Great Stuff!!

DMC

[74Argosy24MH]

I posted this for someone asking about ribs. This is a 74 motorhome, but probably very similar. Between the ribs was fiberglass batt insulation and a lot of empty space.

I am going to put paneling on my walls. First try I put a piece against the floor and wall, tried to push it into the curve and it broke. So I made a buck that I can clamp the sheet to on what will be the bottom and slowly pull it down using 2x4's and pipe clamps. Have done 2 scrap sheets this way and neither broke. I am now debating if it would be better to cut the window opening before clamping or after. Before I see the weakness of the opening in the panel might affect it, after it would be a pain to make the opening.

There is no nice 16-32-48 spacing on the ribs, you can see from the rivet lines outside. An 8 ft sheet does go from my floor to the aluminum trim that runs front to rear.

I also put foam weatherstrip behind a piece of 1/8x2 aluminum strip over each rib. This hopefully will be a thermal break and give something a little wider to mount on.

John

[thenewkid64]

John,

the foam tape is something that even the Factory is doing now. I have also seen that most of the newer trailers have a foam backed vinyl, or a glued on fabric wall covering. The explanation I got was that it allowed for more rivets on the inside to make the inner shell stronger and better insulation. I agree with the better insulation but the more rivets to make it stronger sounds like build it faster and cover up the sloppy rivet job. Besides with all the rivets covered how will you know if you have an inside skin coming off? I like the idea on the paneling, but would it be easier to reattach the inner skins and veneer it?

http://cgi.ebay.com/ws/eBayISAPI.dll...tem=2059188576

Brown pop rivets are available or could be made.

You would only need to veneer the exposed sections of the walls and there would be no weight penalty. Just a thought...

[74Argosy24MH]

Too late, all but one sheet has been used in filling openings here and there on this and other jobs I have done since starting. It is wood or foam for me now.

One of the things I thought about before I did this was what I was doing to the integrity of the shell by only having one skin. A lot of the strength comes from the double wall. When I did my floor I replaced the 1/2" plywood that is in the bottom track, then glued and screwed another piece of 3/4" on top. Both are screwed to the frame.

I want to do the interior with 16 ga. 1x1 steel tube for frame work and tie this to both the floor supports and the ribs. This should make up for the loss of strength by not having 2 skins.

In reality veneer would be a better way to go. Unless you tie it all together, I don't think the shell would withstand just removing the inner aluminum and paneling over the ribs.

John

[Dave Cole]

i must have missed something--is there a second layer undernieth the textured white vinyl on the inside of my '69? if i understand you guys right, the 74 argosy had (from the outside heading in) the outer aluminum, then ribs and fiberglass, then sheet aluminum (inner skin) and then wall covering?

i am probably confused--i usually am.

I am starting to like the 'veneer the existing material' idea though--that is something that could be jobbed out to someone who really knows what they are doing.

three points re. veneer though: is the coefficiant of expansion of the wood being differant than what it is glued to going to make it blister/crack? if it is glued to the skin before application, will it be able to make the bend without buckleing? lastly, will contact cement even stick to the inner skin?

[thenewkid64]

Dave,

The textured white vinyl is attached to alumimum sheeting that is riveted to the inside of the ribs.

I would think if you used contact cement that the adhesive would retain enough flex that the expansion/contraction of the sidewall would not crack it. But that is a guess on my part. I have not measuerd the dimentional changes that my MH goes through in a day in the sun. I would think that the veneer would bend without breaking due to the thin nature of the veneer. And I thnk that contact cement wil stick to just about anything, you would have to scuff the vinyl for a good bite, and use a good brand like 3M but It should work.

I have not tried this but I am becoming tempted myself!

[74Argosy24MH]

There are only three layers- the outer skin, the ribs/insulation and the inner skin. The white vinyl is laminated to the inner skin and effectively one layer.

The differences in expansion of aluminum and wood is a good point. A cabinet maker might be able to help on that one. There definitely will be a wide temperature range to consider. It is possible that by making small enough pieces a pattern could be made that would allow this to happen without damage.

The veneer will bend around the curve. I have seen furniture with far smaller radius than the walls of the Airstreams. The contact adhesive will stick. You will have to make sure the vinyl is prepped correctly, clean, scuffed, etc.

John

[PeterH-350LE]

John, it sounds like you have invested a lot of thought in it.
As you know, most of the windows are not riveted to the ribs , just to the skin. Part of the integrity of the shell comes from the interior skin.
My attempt in using contact cement failed miserably in the Texas summer conditions. At 120 degrees the contact cement softened up enough to let go. It was a big mess.
Wood paneling instead of the interior skin is asking for trouble sometime down the road, imho. Condensation and the unexpected leak would do a lot of damage.

[74Argosy24MH]

Peter

I am going to use a 1/4" layer of styrofoam insulation on the back of the panels, one more attempt to isolate it from the aluminum. I do have a fair amount of concern for moisture destroying the panels, more from the cold transferring across the ribs and then condensation. Before I tore it completely apart there were several days when I went out to work and there was a perfect outline of the ribs on the inner skins. Kind of neat to look at but also very educational.

Leaks should not be a real problem. The whole cavity between the walls is polyurethane foam insulation, sort of an industrial version of Great Stuff in the cans. It fills everthing and everywhere. I missed a couple of rivet holes and it let me know. I pulled all the windows, the door frame, generator opening, anything that went through the outer skin and resealed them. We are in the remnants of the hurricane now, some pretty heavy wind and driving rain and it is not leaking, cross my fingers, knock on wood.

It is interesting what you said about the contact cement. The highest it got inside there this summer was 127, I have been watching to see what the extremes will be. What contact cement did you use? I put some of the styrofoam sheet on FRP that is on the curves in the rear and used 3M 77. If it doesn't hold it should not be a major disaster as it is sandwiched between the FRP and the foam/ribs, but would be interesting to know if I should change.

John

[PeterH-350LE]

John,
If you are talking about the 3M77 spray adhesive, you need to investigate its holding properties under extreme conditions. It is even weaker than 3M's Contact cement. I would laminate something to a piece of aluminum and see what happens at 140/150 degrees. I am not real sure what the temperature of the skin and the ribs is, when you see 120 degrees inside.
I tried several brands of contact cement and they all failed.
One was Dap's weldwood, the other TACC-T206 (high heat resistant). There must be products out there suitable for interior trailer conditions. The only one I found so far is 3M's Trim and decal adhesive, but it only comes in a small tube.
Interior wood walls:
Have you ever walked out to your trailer and noticed a window you left open. 'Darn, I know I closed all the windows'
Driving rain will push water up your weep holes and down the wall. I drove into a super cell ones in New Mexico and could not believe the water coming in from the horizontal wind.
The next leak in your water lines. Yes, I know most of yours are probably new, so are mine. Thats why I 'never' drive with the water pump on, nor leave the MH unattended plugged into to a water line.

[74Argosy24MH]

Thanks for the tip on the contact cement. I have a small piece if FRP/styrofoam that is a filler between 2 8 ft sheets. It has been there through some hot days. I will pull it and freeze it, if it has not seperated already. Looks like it may be time for more research.

I understand your point about the plumbing leaks, open windows, etc. I will try not make a novel out of this, but so you understand what I found when I got it. I paid $3500 for it. When I drove it home I had never heard so much noise in my life, the low rider Hondas don't have amps big enough to drown out the racket. In quite a few places the cabinets had pulled loose from the skin, and rubbed through the vinyl. I don't know how your cabinets are built, but mine were paneling inserted into extrusions, then pop riveted. The pop rivets only went through one side of the extrusion into the paneling. I can see clamping the wood inside the extrusion, but trying to rivet it to the extrusion?

So I decided to gut it and start over. Then I found the real mess, the dry rot and holes in the floor, inner skins trashed. Both inner end caps were more cracks than good. It had been well abused through it's life, and to me was easier to start over than repair. I hated to put all the time and money into cabinets and have the walls look the way they did.

I have moved the roof AC to make room for solar cells, and am going to make some interior layout changes. These will leave holes that will not be easy to disguise. Bare aluminum is an option for the skin, but I haven't seen vinyl clad in years. The only option I could come up with is paneling or one of the other home wall coverings. I considered upholstery (which I am going to do in the bedroom), but the upkeep is too much overall.

I also look at it this way- when I screw up and trash a piece, I have a template to start over with. It won't be nearly as hard to replace as it was to figure out in the first place.

John

[Dave Cole]

good point you guys make about leaks within the walls. You are right, this thing WILL leak, and i had better design for it.

The vinyl in my '69 Tradewind is ugly enough, and the prospect of an alluminum trimmed, yellow birch bent plywood interior is beautiful enough that i am willing to try to come up with a design. I figure, what the hell, if they make the interiors of sailboats out of wood, i should be able to figure out a way to do it in an A/S (especially with some help with you guys)

I just need to make sure the water that leaks and condenses inside the the wall can't get to the wood. how about plastic or tyvek beween the ply-wood and the ribs/ fiberglass insulation?

also, regarding sprayed in foam:
I am resistant to useing foam insulation generally, because it tends to hold moisture in place against walls and because i hate making things that are then hard to modify or fix, but in this case it might keep any leaking moisture against the outside skin and away from the wood. foam would also make the trailer a lot stronger overall, and harder to dent.

[thenewkid64]

Another option in addition to the tyvek would be to coat all 6 sides with a polyurathane finish so that the wood is sealed and the possibility of moisture penatration is minimal. This will add to the weight and you may want to form the panels prior to install so you are not flexing the finish and causing it to crack. Just my $.02 worth.....

[74Argosy24MH]

Dave

Tyvek will pass moisture, not quickly, but it is pervious. Brett's idea of sealing all edges is good, I did that on my floor. Think seriously about some type of thermal break between the wood and aluminum, I believe you will have more trouble from the conductivity of the aluminum than leaks within the walls. On cool damp days I could see lines of moisture from the ribs on my inner skin. To me that meant that wood against the aluminum was going to be like a sponge.

The foam did stiffen the body a lot, even helped a little with sound. It is easy to fix, a sharp knife and a putty knife and you can pop a piece right out to do a repair. Fill the hole with some from a spray can and you never know it was done.

Another thing besides leaks and water in the walls I would think about early on is the loss of strength to the shell by removing the inner skin and how you can compensate for that. It is like peeling the paper off one side of a piece of cardboard when you remove the inner skin.

If you are planning on using paneling my experience says you are going have to form it before you install. There is a luan that is used for making curves that would work. I like the idea of that and veneer if I can find an adhesive that would hold, maybe one of the polyurethanes. Research time.

John

[Dave Cole]

good point about tyvek being semi-permiable--will consider plastic instead. also good point about the poly. as far as the comment about stability after removal of the inner skin goes. you are right about removeing the skin, but i'm not leaving it off or driveing anywhere without it. i will be replaceing the 33 year old vinyl with new hardwood plywood as well as a liner of spray foam and the same number of rivets that A/S used originally. i may be wrong, but my figuring goes that i will most likely gain structure.

as far as bending and installing the plywood, i will go to the experts. we have a high-end plywood mfg. here in providence--allied plywood. when i get completely demo'ed and pretty well planned out, i am going to go over there and see if i can enlist their help. you know offer to give them a really nice set of 8x10 'before' and 'after ' pictures to hang in the office as a thank you for the help when i get done.

as we all, know everybody loves an A/S

do you think that sufficiant moisture would build up between the polyurathane and the tyvek/plastic vapor barrier to cause problems?

re the cold transfer along the ribs condensing lines on the wood, that's a real good point-- need to line those ribs with some kind of thermal barrier. what kind of a thermal insulator can you line the ribs with that still allows you to pop rivet into them?

[74Argosy24MH]

The vinyl on the inner skin is laminated to .050 (or close) aluminum. It is like a super duty contact paper on the metal. These pieces go from the front to rear main ribs. This along with the curve of the body has to make an extremely strong sructure. It is probably overkill for what is needed, but is what allows these to last 40+ years. One problem I see is that the ribs (on mine) were not attached to the sill. The skins were used to provide the strength. Paneling (or even hardwood plywood thin enough to follow the inner curve) really isn't designed to be a structural element. You will also loose strength because the sections will run vertically as opposed to the one piece front to rear horizontal runs. When you do your cabinetry I would try and make a few heavy floor to ceiling partitions where you could tie to a rib.

Before insulating I made sure I had no leaks. I resealed all openings and let it go through some pretty good storms just to make sure. Before Dow bought the outfit that made the foam I used, they had a good website with a Q&A section. One of the things they touted was the sealing properties because of the way it expands to fill the smallest hole or gap and they were right. I can't imagine there will be a lot of problems with leaks or moisture buildup. I like the idea of sealing the panels with polyurethane, but don't think you will need a vapor barrier. If you are concerned that moisture is going to be a problem I would use small vents near the top and bottom of the panels . These could be inside a storage area or closet and not normally visible.

The ribs are only about 5/8" wide where they attach to the skins. I put 1/4" thick self adhesive foam weatherstrip (closed cell, no moisture transfer) on the ribs, rolled some 1/8x2 aluminum to match the curve and pop riveted it to the rib/weatherstrip. That also gave a 2" wide piece to mount the paneling.

John

[59er]

Dave or John,


Did you guys ever complete the wood interiors and determine how the condensation affected it?

I am considering adding an 1/8 layer of birch ply over the inner aluminum skin and am interested in what came about. I considered using a layer of the really thin sheet styrofoam that they put under pergo 'floating' floors, so that it would add a layer of something between the wood and alum. and help even out all of the differences in the panels and rivets...

thanks.
of course, pictures would be a bonus!

[A-Merry-Can]

Originally Posted by Traveller

I am considering adding an 1/8 layer of birch ply over the inner aluminum skin and am interested in what came about. I considered using a layer of the really thin sheet styrofoam that they put under pergo 'floating' floors, so that it would add a layer of something between the wood and alum. and help even out all of the differences in the panels and rivets...

this sounds like what i want to do to our traveller when i get her back together. did you ever end up starting this? i'd definitely be interested in seeing a step by step on installing wood. especially in the end cap area where the compound curves are.

jordan

[B Stover]

Dave:
I'm considering doing the same thing. Besides veneer or laminate what is thinnest wood sheeting that you can get?
Bernie