New NeoAir too good to be true?

by **Buz Groshong** » Thu Mar 26, 2009 8:17 pm

Norco17 wrote:

If you have a baffel inside the mattress it kills the internal convection cell. Yes the matress still insulates but not as good as one where the air inside can't move. Ideally you would have a self inflating closed cell mattres, but it is kind of hard to inflate closed cell foam...though some may try.

Generaly heat does transfer up like you say, however that is because normaly heat decreases as one moves up. In the case of someone sleeping on snow the heat will move away from the source(read the heat will move away from the body) therefore in this case the heat does move downward.

Not really. Heat moves away from the source by radiation and by conduction; heat does not move downward by convection. Radiation transfer is fairly minimal (would be better if the inside of the air mattress was reflective and worse if it was black) and the air doesn't conduct heat well. Adding foam, down, or whatever may make the air mattress more comfortable and may help eliminate thin spots (that can be cold spots), but it won't improve the insulating qualities of the air mattress.

by **norco17** » Thu Mar 26, 2009 9:51 pm

Buz Groshong wrote:Norco17 wrote:

If you have a baffel inside the mattress it kills the internal convection cell. Yes the matress still insulates but not as good as one where the air inside can't move. Ideally you would have a self inflating closed cell mattres, but it is kind of hard to inflate closed cell foam...though some may try.

Generaly heat does transfer up like you say, however that is because normaly heat decreases as one moves up. In the case of someone sleeping on snow the heat will move away from the source(read the heat will move away from the body) therefore in this case the heat does move downward.

Not really. Heat moves away from the source by radiation and by conduction; heat does not move downward by convection. Radiation transfer is fairly minimal (would be better if the inside of the air mattress was reflective and worse if it was black) and the air doesn't conduct heat well. Adding foam, down, or whatever may make the air mattress more comfortable and may help eliminate thin spots (that can be cold spots), but it won't improve the insulating qualities of the air mattress.

I forgot about that whole temperature inversion thing. Thanks for the correction.

by **kozman18** » Fri Mar 27, 2009 12:30 am

nartreb wrote:The big advantage is obvious: packed volume is one-third that of the Z-lite. This converts the pad to an inside-the-pack item, if desired.

True for the Z-Lite, but not much smaller than the Pro-Lite (which can fit inside a pack). Still 50% more expensive, and not as warm.

by **Buz Groshong** » Fri Mar 27, 2009 1:41 pm

Goldenhopper wrote:

Buz, I think they are using an internal radiant layer (like a space blanket) just below the top of the mattress to reflect any radiant heat. Does that sound reasonable?

I didn't see that one, but it sounds like you are right. A radiant barrier needs to face an air space to be effective, so one on the inside of an air mattress should be very effective.

by **TheOrglingLlama** » Fri Mar 27, 2009 1:47 pm

I recommend

if you want to stay warm at night while camping :mrgreen:

by **MarthaP** » Fri Mar 27, 2009 2:13 pm

Dear Orgling,

Midnight at the oasis
Send your llama to bed....

:wink:

by **TheOrglingLlama** » Fri Mar 27, 2009 3:36 pm

by **DukeJH** » Fri Mar 27, 2009 5:42 pm

My Exped7 packs substantially smaller than my ProLite4, down to the size of a 1 liter Nalgene. Both are inside the pack, but the Exped packs smaller and gives me substantially more space between me and the ground thus alleviating the bony hip problem. The exta thickness also provides more insulating volume (loft). It was a gift so the price was absolutely right.

My Z-lite has been an outside the pack item and will likely remain so.

by **emppeng27** » Sat Mar 28, 2009 1:29 am

I've had the Exped Downmat 9 for a year now and can say it is one super-comfy/super-warm pad. It is definitely heavier than the other pads out there though. I use it for sleeping in the back of my truck, at camps where I don't have to hike much or will be there a long time, or for expedition use. It is expensive (I got mine for almost half off and it still wasn't cheap) but worth it. I use my prolite4 3/4 for climbs to save weight.

by **woodsxc** » Sat Mar 28, 2009 7:11 pm

DukeJH wrote:My Exped7 packs substantially smaller than my ProLite4, down to the size of a 1 liter Nalgene. Both are inside the pack, but the Exped packs smaller and gives me substantially more space between me and the ground thus alleviating the bony hip problem. The exta thickness also provides more insulating volume (loft). It was a gift so the price was absolutely right.

My Z-lite has been an outside the pack item and will likely remain so.

My Ridgerest goes inside or outside my pack. If I put it outside, it goes rolled up under the pack lid. But if I want to have it inside, I roll it really loosely and put it vertically inside the main compartment of my pack with my tent and other stuff inside it. Helps stiffen the pack and keeps the pack profile narrower (less snow dumped down the back of my neck).

by **OJ Loenneker** » Sun Mar 29, 2009 2:51 am

by **DukeJH** » Mon Mar 30, 2009 6:34 pm

Wrong thread! :twisted:

by **woodsxc** » Tue Mar 31, 2009 5:04 am

DukeJH wrote:Wrong thread!

I'm not mad.

by **mtelephant** » Thu Apr 16, 2009 7:07 pm

Well, they are too good to found anywhere. The long has yet to be produced, only the regular and short so far.

How many people here have one? Is it comfy? Is it as light and small as claimed?

I really want a large one but for now I am just waiting.

by **mtelephant** » Fri Apr 17, 2009 1:28 am

goldenhopper wrote:Not sure where you are, but I made a few calls the other day to REI, Sport Chalet and Adventure 16 in the Los Angeles area and none of them had any of the sizes in stock. A16 said they will likely not get them until the start of summer.

I spoke with Cascade and they said they are sending them hand over fist in short and regular. They are even having some sent from Ireland to meet US demand. So they are out there - just no large yet.

New NeoAir too good to be true?

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