[pct-l] Stoves and Winter

["David B. Stockton" <davstock@tiac.net>]

Hi folks.

"Reynolds, Tom" <reynolds@ilan.com> wrote:
(snip)
<<
4 degrees] but the stove still lit promptly. To me, an non-winter camper,
this seems a rigorous test. I personally would keep the canister in the
sleeping bag foot so I don't think -10F is very realistic.

What do you winter campers say? {I can light THIS stove in a tent without
difficulty)
>>

Although I have engineering training and a reasonable amount of field 
experimentation experience, Tom, I don't work with energy/heat calculations 
every day, and moreover, calculations can only carry one so far.

With the number and magnitude of variables in operating portable stoves in 
the field, any calculation, no matter how sophisticated, is virtually 
meaningless without supporting, well-controlled experimentation.  Not to 
say that experiments aren't fun, though.

I do have some experience with stoves in the winter, but mostly with the 
MSR XGK.  I can say that winter camping is completely different than 
"freezer camping" -- there is nearly no overlap.  Things happen in cold 
weather (read: below 0 degrees F) that cause unexpected factors to be far 
more significant than BTU calculations.  Parts contract at different rates 
depending on their material composition.  Manipulation factors (working 
things with mitts on) become more important.  The lubricants one uses 
become important.  The significance of fuel spills changes as fuel 
volatility changes.  The psychological stress on the user is very 
different.  The air, stove, fuel and tester are at the test temperature.

Here are three anecdotes:

At one week-long winter mountaineering class in the Adirondacks that I 
participated in (1994), we started at -27 degrees F.  At that temperature, 
the only stoves (in our class of at least 20 people) that would light (not 
"be efficient" -- we're just talking start up) were the MSR Whisperlight 
and the XGK.  I don't know what other stoves people brought, though.  The 
XGK was much easier to start and run than the Whisperlight.  I was able to 
run my fairly well-maintained XGK burning white gas or unleaded (I forget 
which) with just about the same technique as summer camping.  One minor 
problem was that the pump piston contracts a little faster with temperature 
than the cylinder, so that it is easier for the piston to fall out -- more 
of an irritation than a problem, especially in comparison to having a 
useless stove.

Another interesting situation occurred on an overnight trip with a North 
Face VE-24 at about -5 degree F.  The silicone spray which I so responsibly 
used on the tent pole mating connectors gummed up due to the cold so that 
the poles wouldn't completely join -- there was a slight gap between each 
so that each of the four poles was about 1/2" too long, making the tent 
VERY difficult to set up (at about 2 AM).

Finally, on another 3-day trip in the Adirondacks at about 5 deg F or so, 
my MSR XGK wouldn't pressurize, leaving us with the possibility of no 
stove; all I had to do was pull the pump piston, replace the leather cup, 
and we were all set.  But it was a sobering time because of end-of-the-day 
tiredness, the cold, etc.  I hope that I would hesitate to put myself in 
that situation with a stove that I couldn't maintain.

My car, on the other hand, I can't maintain; but then I'm now a AAA member 
and I don't use the car for hiking the Sierras in winter.

I personally wouldn't count on my stove having been in the foot of my 
sleeping bag until it has reached 60 deg F or so.  There are many 
situations in which that precondition wouldn't be achievable, including 
(obviously) day trips without a sleeping bag.


"Reynolds, Tom" <reynolds@ilan.com> also wrote:
(snip)
<<
My tests are designed to qualify propane/butane stoves for winter camping
and emergency use for winter dayhiking. I am going snowshoeing in Yosemite
and want something in my pack that will boil water if I somehow become
disabled and need to bivouac overnight.
>>

 -- and --

(snip)
<<
This data dispels a couple of myths. First a propane/butane mix works well
>>

Tom, I personally don't think that the tests you describe are of the rigor 
that would qualify a stove for such conditions, especially if you are 
trying to "dispel myths".  In the situation that you have described 
("winter dayhiking. I am going snowshoeing in Yosemite"), it is likely that 
you would see temperature extremes, snow, wind, ice, rain [great 
snowshoeing! :*) ].   You also are presuming that you are disabled, so that 
you are under high stress; you may be injured; you may have difficulty in 
controlling your bivouac site and conditions; and you are likely to be at 
least mildly hypothermic, so that you may have trouble manipulating things.

Here is a description of some things that I would consider when trying a 
stove for the use that you described (qualification ala Underwriter's 
Laboratory is not in the picture). I presume that the tester is not an 
experienced winter camper.

To the tester:
1) Do your testing in the field overnight on a few trips with buddies along 
that are winter campers.
2) Borrow, rent, or buy an XGK.
3) Bring the XGK as both a backup and as a quasi-control.  Use it and your 
other stove(s) until you are completely familiar with it before your field 
tests.  Make sure it is well-maintained and works properly before you 
start.
4) Bring also whatever stove(s) you want to investigate.
5) Bring a field thermometer and a pencil (not pen) and take notes.
6) Set up some independent variables such as:
		ambient temperature
		starting temperature of the stove
		what kind of hand protection you're wearing
		what the Beaufort scale wind speed is
		what kind and intensity of precipitation you are experiencing
		whether or not you're using a wind screen
		whether or not the stove is hot/wet/frozen/snow-covered when you start
		the time of night
		your frame of mind
		how many miles you've snowshoed that day
    Ignore fuel usage and in-tent startup until you've investigated the 
factors above.
7) Experiment a lot with the XGK and your test stove(s).
8) Take lots of notes until your buddies are tired of hanging around camp, 
then take more.
9) Go home and type up your notes, seeing if you can read them and trying 
to remember what they mean.  Field note-taking is more difficult than 
laboratory note-taking.
10) Draw some tentative conclusions, pick a stove, then take it and an XGK 
on a few more full overnight (non-emergency) trips without your buddies as 
backup.
11) Take more notes, etc.
12) Tell us what you find.

I also highly recommend that while you're out with your buddies that you 
test your emergency bivouac technique and gear, including using your bivy 
sack or whatever it is that you consider to be your emergency equipment. 
 Don't use anything that you wouldn't bring on the target day-trip (make a 
list before you leave, then change the list when you actually have to sleep 
that way).  Put everything else in your buddy's tent.  Have your buddy set 
an alarm and check on you in the middle of the night to make sure you're 
not hypothermic.

By the time you finish all the testing, Tom, you will be a winter camper, 
will have had a great time, and will know at least one stove that is 
suitable for your trips!

Of course, I'm not applying these comments in any way to a through-hike of 
the PCT.

-- Dave

David B. Stockton
davstock@tiac.net





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