Interesting point. So what type of insulation do aircraft use.
Closed cell foam is used in the building industry all the time and can be sprayed horizontal ,vertical , and upside down . I would not think application is a problem ( not talking Great Stuff , but real stuff )
Hi ticki2; That is a good question for Doorgunner. I believe that most aircraft uses blanket type foil insulation. Send him a Pm and you will most likely get answer that you cannot afford it.
Addressing the spray or pour foam issue, please read some of my previous posts in reference to expanding foams. It must be closed cell or else it will absorb moisture which negates the "R" value by increased transfer of temps heat or cold, by contact.
Hi ticki2; That is a good question for Doorgunner. I believe that most aircraft uses blanket type foil insulation. Send him a Pm and you will most likely get answer that you cannot afford it.....
Thanks, "Boatdoc"
That was the answer I got from a friend of mine who is an A&P mechanic. It's good stuff but the cost is very high.
Hi ticki2; That is a good question for Doorgunner. I believe that most aircraft uses blanket type foil insulation. Send him a Pm and you will most likely get answer that you cannot afford it.
Addressing the spray or pour foam issue, please read some of my previous posts in reference to expanding foams. It must be closed cell or else it will absorb moisture which negates the "R" value by increased transfer of temps heat or cold, by contact.
Thanks, "Boatdoc"
I was talking about closed cell foam , it is also used in refer trucks and trailers . I happen to have an old military trailer ( 1958 ) that is built with a sandwiched wall , inner layer of alum , 2" foam insulation , and alum outer layer . While customizing it into a work trailer I had some of the wall section open . None of the foam had pulverized after 50 years. This is a trailer that was ment to be dropped to the ground by a chopper and hauled where no roads exist.
I was talking about closed cell foam , it is also used in refer trucks and trailers . I happen to have an old military trailer ( 1958 ) that is built with a sandwiched wall , inner layer of alum , 2" foam insulation , and alum outer layer . While customizing it into a work trailer I had some of the wall section open . None of the foam had pulverized after 50 years. This is a trailer that was ment to be dropped to the ground by a chopper and hauled where no roads exist.
Thanks for the tip on doorgunner.
Hi ticki2; You are correct. Military used a closed cell foam. The truck structure was made rigid however, this is why it withstood the years of use.
If I am not mistaken it was 4 lbs weight which is hard to destroy to begin with. Some foams did contain linear poly compounds making them more resilient, although I am not sure what the military used back in 1958. If you pay attention to tests results performed by Zep, you will realize that in order to improve on basic insulation is not that simple of a task. It is not cheap or easy to install properly and end result will vary under different conditions.
To be honest [without offending anyone] some of the vintage AS's twist and buckle on bad roads because many of them do not have a sufficiently stiff frame platform, or/and the attaching points of the shell to the frame need attention. How long do you think 2 lbs density foam will survive under those conditions? Urethane foam in dust form can create a very unhealthy condition inside your AS. You will be breathing it in, because it is light enough to get airborne every time you stir the air inside. And yes, I know that there are inner walls. But, the inner walls do not offer a perfect seal in many places.
We can take this insulation issue into the infinity, but the question will still remain, why O why?
You want an air space? Glue in urethane 3/4" foam strips to the outside skin or place glass insulation first with vapor barrier facing inside, then cover it with bubble foil glued in at the edges, and even if you like add another layer of thin glass insulation on top of the foil. It may make you happy because
you just gained a whole 1 point in "R" value. I personally, do not even like the idea of fiberglass batting against inner wall unless it is sealed by paper backing, simply because sooner or later glass will become airborne. There is no doubt in my mind, what those extensive experimental tests which Zep is performing are telling me. Too many variables, too much difficulties not enough results. If anyone chooses to discredit Zep's findings then prove him wrong. In the mean time let's just go camping. Thanks, "Boatdoc"
Hey Zep, here's an idea for you. Instead of the canned spray foam stuff, have you thought about looking for a commercial insulation company that might spray a test box for you with something similar to the stuff I referenced back in post 29? I suspect that if you approach one of them and explain what you are doing, they may set you up for free. You could maybe go to one of their jobs and fill the "wall" while they are working on a building somewhere. After all, you don't need much foam to fill that small test wall.
With recent thirty nights below zero still near and dear I confess heat and insulation are the only things I was to talk about!
Want to hear about Ultra-High-Bonding 3M foam tape and the 1/16th aerospace silicone sheeting soon to be delivered that will get installed as thermal barriers over the shell rib to interior liners interface?
Or the stainless steel heat exchanger and insulated tank I'm trying to shoehorn in to use with solar hot water collectors I have stashed to provide non-propane heat when boondocking?
Any how - one spot I see foam-in-a-can being good for is to drill and fill the shell ribs to keep twenty little chimneys from allowing condensation cycles from occurring or the hard-won heat I'd trying to bottle up from touching an uninsulated air space on my side of the shell!
..Want to hear about Ultra-High-Bonding 3M foam tape and the 1/16th aerospace silicone sheeting soon to be delivered that will get installed as thermal barriers over the shell rib to interior liners interface?
...
Any how - one spot I see foam-in-a-can being good for is to drill and fill the shell ribs to keep twenty little chimneys from allowing condensation cycles from occurring or the hard-won heat I'd trying to bottle up from touching an uninsulated air space on my side of the shell!
I hope you got three dogs!
Yes, want to hear right now!
Agree on using spray-in foam for the little leaks around perforations.
I'd be careful with some of the spray foam insulations...if you overdo them or apply them unevenly they might expand and oil can the aluminum skins. I recently had a project that the GC applied the foam insulation too dense inside the walls and it bowed the gypboard once it was finished expanding. The gyp had to be removed, the insulation trimmed and then new gyp used...did not make his day!
Shari
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I'd be careful with some of the spray foam insulations...if you overdo them or apply them unevenly they might expand and oil can the aluminum skins. I recently had a project that the GC applied the foam insulation too dense inside the walls and it bowed the gypboard once it was finished expanding. The gyp had to be removed, the insulation trimmed and then new gyp used...did not make his day!
Shari
I have seen it jamb windows and doors shut when trying to use it in a cavity . The inner and outer skin on an AS is nowhere near stiff enough to try and spray between them , the inner skin should be removed . I would think the only time foam would be considered is on a full monty.
Looking at other posts showing clean and even polished interiors has made me ask if the most perfect polished foil radiant insulation is already there - the inside of exterior shell 2024 aluminum???
Lessoning oxidation and texture with a quick polish and fighting off remaining adhesive left on it before making up the "air gap" certainly would mean a more insulated section.... right?
Looking at other posts showing clean and even polished interiors has made me ask if the most perfect polished foil radiant insulation is already there - the inside of exterior shell 2024 aluminum???
Lessoning oxidation and texture with a quick polish and fighting off remaining adhesive left on it before making up the "air gap" certainly would mean a more insulated section.... right?
Well, sorta. There is virtually no part of the interior of the walls in mine that is clean and "polished". The interior walls are actually painted on the back. The inside of the exterior skin is covered in the glue substance that originally was used to attach the pink stuff to the shell. In other words, there isn't much there to reflect anything, if that's what you mean.
I'd be careful with some of the spray foam insulations...if you overdo them or apply them unevenly they might expand and oil can the aluminum skins......
Shari
The thread that I mentioned above discussing the spray foam stuff contains a post from a fellow who actually had this type of problem. I believe he blamed it on heat, IIRC. Your scenario was more likely the problem, I'll bet.
The reason that I bring up the spray foam insulation (professional grade, not the canned stuff from HUD) is that this post in the previous thread is the only instance I've read on this forum of anybody actually using the stuff in an Airstream. There may be others, but I havn't found them. That sort of speaks volumes to me. Still it would be nice to see how it stands up against the other methods Zep is testing.