| Author |
Message |
nelson thomas (205.188.209.8)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, December 06, 2003 - 9:38 pm: | |
I will be getting my 4104 hot spray foamed soon. I saw a post recently that reminded me that heat and cold will transfer through the ribs to the interior. what would be a good way to deal with this. I'm 6'2" , headroom is at a premium.
Nelson, Knoxville |
TWO DOGS (66.90.216.103)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, December 07, 2003 - 6:59 am: | |
has anybody ever drilled a hole in the tubes and filled them |
Stan (24.67.45.35)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, December 07, 2003 - 8:13 am: | |
If you have square tubing the problem is not the heat transfer through the air inside the tube but the large surface area exposed to the outside skin transfering heat from the inside skin. If you can afford the reduced interior space you can insulate between the tube and your inside plywood. |
Gene Lewis (Genelewis) (66.193.8.152)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, December 07, 2003 - 12:47 pm: | |
I filled all the tubes on my eagle when I was insulating my conversion. I did drill two holes one to fill and one to allow for overflow that assured me that the foam filled the tube completely. I placed the holes about 18" apart. I used Great Stuff and am pleased with the way it turned out---that's my .02 cents worth. |
TWO DOGS (66.90.217.99)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, December 07, 2003 - 1:27 pm: | |
great minds work alike |
Geoff (Geoff) (66.239.48.68)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, December 07, 2003 - 7:32 pm: | |
What good does filling the inside of the tube do when the heat heats the whole tube (the metal)? Like Stan says you need to insulate OVER the tube to keep the heat from radiating into the inside of the bus. |
TWO DOGS (66.90.210.166)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, December 07, 2003 - 7:39 pm: | |
"I" think it would...plus...no rust |
Gary McFarland (Gearheadgary) (64.134.135.51)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, December 07, 2003 - 7:51 pm: | |
I have been told that the spray foam uses an acid in the catalyst that will attack metal.
I have considered using spray-foam, but everything in my bus is well primed.
I don't have any facts to support this, but I'd advise extreme caution in filling a potentially uncoated structural member with spray foam.
Gary |
Tom Caffrey (Pvcces) (65.74.64.127)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, December 07, 2003 - 7:54 pm: | |
And then one fellow put something like a
Saudi roof on his. The way I remember it was that he placed a layer of 1/2" or so thickness of styrofoam over the outside of the roof, and then placed a layer of aluminum skin over the styrofoam, which he anchored at the drip lips.
He was trying to cut down the heat at the hot spots in the ceiling caused by the heat conduction of the frames between inside and outside. He said that it worked really well.
I think that he only fastened the middle sheets at the drip rails, not at the seams running over the top. I don't recall what he did on the ends.
For what it's worth.
Tom Caffrey PD4106-2576
Suncatcher |
BrianMCI96A3 (65.40.154.50)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, December 07, 2003 - 7:59 pm: | |
Saw a guy's MC-9 conversion on the internet, he drilled and foamed all his tubes...
I dunno though, he swiss cheesed all the tubes.
Might be effective insulation-wise, but did he compromise his structural integrity?
Brian |
Tony (64.215.196.161)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, December 07, 2003 - 8:41 pm: | |
Tom
I believe that was George Myers that Insulated his Gillig bus like that |
wjeeppc (64.136.26.228)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, December 07, 2003 - 9:10 pm: | |
Depends on how far you go inside I pulled off the entire shin inside of my MCI5 and sprayed the form in every channel lots of rivet holes to leak from no problem with the fome staying liqued.Could not put my hand on the roof or channels before this on a hot day.After cool to the touch.Side benefit big noise reduction better insulation.If it is done right there is no moisture left to form rust.Go for it you wont be disapointed. |
Gary McFarland (Gearheadgary) (64.134.135.51)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, December 07, 2003 - 10:19 pm: | |
I can't find any references to Polyisocyanurate causing rust, however I found hundreds of references to thoroughly priming before installing polyiso.
I was told once that the catalyzing agents in polyiso foam cause very rapid oxidization, no moisture necessary.
I am not a chemist, nor do I play one on TV.
Gary |
Ted Elder (65.35.227.96)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, December 08, 2003 - 1:39 am: | |
My bus is spray foamed with the ribs uninsulated and I did notice some condensation on the inside the bus portion of the rib when it was cold outside and warmer inside. This would be more of a concern than heat transfer as far as I am concerned. However, by the time you put plywood, which would act as a thermal break anyway, and some ceiling material (in my case 1/2" foam and vinyl), I don't think the heat gain or loss is a major issue. But insulated would be better for sure. Ted |
Stan (24.67.45.35)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, December 08, 2003 - 8:24 am: | |
Ted: The condensation is caused by the thermal tranfer. To get a complete thermal break (without much insulation value) you can screw the interior plywood to the framing, countersink the screw heads and then glue a second layer of plywood to the the first one. There has to be no metal to metal contact between the outside skin and the interior finish.
This is a much bigger problem for people who have to heat their coach than for people who only use A/C. |