View Full Version : Aluminum foil in clark Pockets
while exploring the temptrol matreial under discussion in another thread, the thought came to me of using aluminum foil as a liner in the Clark storage pockets which should reflect back your body heat. Has anyone tried it?
I wonder if you used aluminum foil as a liner and then put inflated ziplock bags between the foil and the inside of the hammock - would that keep the heat from the bags and your body from escaping, giving you and effective dead air space? didn't they do something like this in the Apollo 13 return trip?
mataharihiker
11-07-2007, 18:07
When I went out last week-end I put the aluminum sheet I have under the Exped...I bought the sheet years ago...it's very thin foam rubber on one side and very thin, flexible aluminum or some sort of shiny material on the other side...weights only a few ounces...I think it helped keep me warm from below...
When I went out last week-end I put the aluminum sheet I have under the Exped...I bought the sheet years ago...it's very thin foam rubber on one side and very thin, flexible aluminum or some sort of shiny material on the other side...weights only a few ounces...I think it helped keep me warm from below...
I was thinking that because "reflective" insulation needs air between it and source of heat that the Clark storage pockets would be perfect, and the aluminum foil would be very light. Add inflated insulated bags between the foil and the hammock bottom in the pockets and you have essentially the air mattress (minus the down insulation inside) with a reflective sheet.
cavediver2
11-07-2007, 18:28
while exploring the temptrol matreial under discussion in another thread, the thought came to me of using aluminum foil as a liner in the Clark storage pockets which should reflect back your body heat. Has anyone tried it?
I wonder if you used aluminum foil as a liner and then put inflated ziplock bags between the foil and the inside of the hammock - would that keep the heat from the bags and your body from escaping, giving you and effective dead air space? didn't they do something like this in the Apollo 13 return trip?
I cant help but think the aluminum foil would tear if used I cant keep it from tearing when cooking. But one of those emergency space blankets might. I thought about putting it right under my sleeping bag. not in the pockets.
A side note I did 19-F last night in a 0-F bag with out anything eles. I had on a lite weight polo pro top and bottom on and smart wool socks and a fleece stocking cap. was toasty most of the time I found that on the left and right of my hip's that they were cool not enough to warrant coming inside or getting something to fix the problem. I used the bug sheild and the outer weather sheild and useing a fluke thermometer I took temp's of 19 degree's at tree and 42 degree in side hammock sealed up and inside the bag was 81 degree's at first check then at first pea break i checked it again before I opened it and it was down 72 inside. If I can find a couple of batteries I am going to take more messurements tonight although it's not suppose to be as cold. I am going to use a space blanket right under sleeping bag tonight.
Well let you all know how I do tomorrow.
P.S I am reading the book Into The Wild great book to read when it's cold out side as well.
P.S I am reading the book Into The Wild great book to read when it's cold out side as well.
The best book to read while in the cold is "White Dawn" - it is a fictionalized account of what happened to an actual ship full of whalers who got caught in the ice around baffin island in 1896. the following spring they were all dead, but the available evidence suggest they interacted with the native eskimo population and were killed by the eskimos due to cultural differences. The book fills in the unkown events with the author's subposition of what happened. It was made into a movie but the movie didn't do justice to the book.
Just Jeff
11-10-2007, 12:41
Into the Wild has just been released as a movie, too - can't wait to see it.
I think aluminum foil wouldn't be worth the hassle.
I'll say it again... Reflective barriers to return radiant heat should have an air pocket on both sides yes, BUT they also should be between the heat source and the bulk of the insulation. That is as close as possible to the heat source.
In other words you want the air pockets on the COLD side of the radiant barrier. The reason for this is that the barrier reflects the radiant heat (think of it like light) back towards the source (you). This keeps the "warm" side of the insulation colder than if the barrier wasn't there. Insulation maintains a fixed temperature difference across a given thickness and for a given heat flow rate. By lowering the "warm side" temperature, the outside temperature that can be maintained is lower.
If you put the radiant barrier outside. Its going to see the lower "outside" temperature of the insulation (but higher than it would be without the barrier). However if it tries to reflect the heat back its trying to "push" it back through all that insulation...
Much like putting a mirror on the INSDIE of the wall... Sure it'll reflect the light that gets there, but you won't see it....