At 22:21 5-01-98 -0500, Dan Clemmensen wrote:
>Arjen Kamphuis wrote:
>> Non-isolated nylon tents do little more than keeping wind and
>> out. The difference between the out- and inside airtemperature is only a
>> few degrees without special action. I've tried with several methods that
>> vary in effectiveness (tips welcome):
>I suspect that the weight of even a tiney "mister fusion" will be more
>than the weight of a reasonable amount of insulation.
Packing volume can also be an issue. Besides: "mister fusion" could provide
so much heat that even at _extreme_ low temperatures (near the top of
Olympus Mons) it would provide sufficient heating whereas insulation has to
get thicker and thicker as temperature goes down.
>I've heard that traditional Korean houses are heated by a wood-burning
>stove under the house whose chimney is a meandering ceramic pipe buried
>in the floor. A high-tech version of this might let you put the burner
>outside the tent while still getting nearly all the heat into the tent.
But how to operate is then? Remote control? You really don't want to leave
the tent if it's forty below and a force 10 wind is blowing. Also the
size/wheight and complexity of the burner goes way up. And burning fuel is
not a longterm option (2 persons can last a week on 1 liter if it is just
used for melting snow and cooking, when fuel is used for warming the
amounts required are two or three times as much).
>> - Forget about the tent.
>> And buy the thickest goose-down sleepingbag you can find (mummie).
>> 1400 gramms of down and a pertex/nylon outershell should keep you
>> happy 'till about 40 degrees below zero.
>As I recall, the problem is to keep the heat in while letting the
>moisture out. There are many super-lighe and cheap insulators, but
>most also trap moisture. What about using a super lighe insulator
>such as bubble-wrap in conjunction with a counter-flow heat exchanger
>to let the moisture out?
Yes, one of the biggest problems is perpiration condensing/freezing on the
outside of your sleeping bag or, even worse, inside the outershell clogging
the down and reducing it's insulating effectiveness. The best solution so
far seems to be a nylon liner inside the sleepingbag, as long as your wear
thermal underwear (the Startrek stuff) it's not too sticky and it ups the
range of the bag by 5 degrees.
>> Even better would be a fusion-pile that uses snow/water/air as a
>You don't need an ambient source. you can seal in enough fuel when you
>manufacure the thing to meet any reasonable energy demand.
Good point, hadn't thought of that.
Steve Witham <email@example.com> wrote:
>How about (I'm not even a beginner), take an inflatable mattress and use
>it semi-inflated to line the inside of the tent wall? If you've got more
>time & money design a tent with inflated walls?
I've used insulated tents in the Arctic, they're great as long as you don't
have to carry them. We had sledges that allow 200 or more pound of gear (as
opposed to 55 in a backpack when your climbing up a hill)
>Mold a quick loose-packed igloo around the tent?
This can (and has) worked if there is loose snow, not too much wind and if
you want to spend time shoveling snow after putting up your tent at the end
of day. This combination is rare if you're in a high&cold environment.
Brian D Williams <firstname.lastname@example.org> wrote:
>>I know, it's completely illogical to want to camp at
>>12.000 feet at newyear but humans do things because they _want_
>>to, not out of neccesity.
>First, Insulation is the key, having a top quality sleeping bag is
>a must, in case of emergency we don't want you going prematurely
>cryonic on us.... ;)
Down is one of the last natural materials that has not been replaced yet by
polymers in outdoor gear (As cotton, wool and manilarope has). I had a
sleebingbag made-to-order by my supplier and have never been cold since
(even at -35C inside the tent). Regrettably it's very vulnerable to dirt
The way hollowfibers are going I would expect it to completely replace down
in 10 years.
>A good insulation choice would be to carry a
>second dome tent slightly larger than the one you intend to stay
>in, (1-2" is best) you erect your tent inside the other, you'd be
>amazed at how well this works.
Ouch! that's another 8 pounds! Not to mention a small heap of cash ;-)
Nice in a base camp that does not have to be moved, but they're generally
not that cold to begin with (well, cold's relative ;-).
If wheight is not so much of an issue an insulated tent that was mentioned
in another post is great (expensive though).
>Is there snow available? Build a Quinzee, which is the loose snow
>version of an igloo. Just make a big pile of snow with whatever is
>available: shovel, snowshow, hubcab, cardboard (were talking
>general survival now) be sure to dig a couple of feet down, the
>trick to a quinzee is that snow forms layers at different
>temps/water content, when you mix it all up in a big pile it will
>freeze solid, and can be easily hollowed out. I've built these at
>the military cold weather facility at Bridgeport Nev at -60 at
I've built ice-iglo's but never a Quinzee. Sounds cool, I mean great ;-)
I'll give it a try when I have a chance (next month maybe).
>We forget what a great insulator snow is, it's only fault
>is that its an insulator that starts to melt at 0 degrees C.
True, when the tent get's half-buried in a snowstorm it's actually warmer.
>Second is to eat properly, no dieting here, calories like crazy...
Yes! Go 4000m+. Eat 4.5 million calories a day and still lose wheight! ;-)
>Third is to drink enough water, cold fools the body into
>dehydration, a liter per 20 kilos body weight per day is needed
>(like the metric bit?) just to stay even, more to stay comfortable.
>The best thing to do if you feel chilled? Drink water (no alcohol).
Tea or soup is even better, water from snow is almost pure H2O and you lose
a lot of minerals sweating all day. People in the himalayas often put salt
in their tea instead of sugar (also because it's cheaper).
>Check to see if the maker of your stove has
>a separate catalytic heating attachment, you'll burn much less
>fuel, much lower emissions and get lots more heat.
Also a good idea! I haven't looked into this for my MSR whisperlite, having
concentrated on minimizing the wheight of my equipment.
>When I was a boy-scout, they used to have these really neat pocket
>catalytic heaters, the big model was the size of a small paper back
>book, you'd state the element, and close the lid (they looked like
>big zippo lighters) then drop it into a red flannel pouch and pop
>it into your pocket. I don't know if there still made, I've got a
>friend who's a scoutmaster checking on it.
I've tried them but I'm pretty sure the energy density is considarebly
lower than high-octane fuel I burn in my stove. My supplier has very small
plastic chemical heaters that are handy as a part of a first-aid kit but
I'm not sure they would be practical for several weeks.
>Now, electricity! There are a number of manufacturers making
>ruggedizeds (sp?) solar panels, you could put it on the outside of
>the backback, and charge while climbing! The beauty of it is that
>it would get more efficient the higher you go!
Yes, when traveling in a sunny climate solarcells are a great way to charge
a battery. I does take a nice clear sky to really get some power though. I
used a laptop in the Andes last year for logistical calculations and
analysis of GPS-data. Six solarcells about the size of CD's powered it in
basecamp and charged the batteries (Also of the GPS and VideoCam). Lotsa
power in good wheather but difficult to store (remember the story of the
So: there seem to be at least some outdoor types here, who's coming on a
climbing expedition to Mars? I believe Olympus Mons is more than tree times
Everest in height! Or maybe we can do something on this planet a bit sooner
;-) Anyone interested in an Extropian/Transhuman hike in the Rockies maybe?
Arjen Kamphuis | - But why do you want to climb so high?
email@example.com | Surely you see that nature never
| meant for you to go above 20,000 Ft?
| - That's why.