Camp stoves: Coleman vs. Brunton
jero...@gmail.com
and I've narrowed my camp stove choices to two, the Brunton Nova
Optimus Multifuel Pack Stove ( http://www.brunton.com/product.php?id=60
) and the Coleman Fyrestorm SS (
http://www.coleman.com/coleman/colemancom/detail.asp?product_id=9775-A25&categoryid=2005
). Anyone have any experience with either of these? Any
recommendations of one over the other (even by brand experience). Does
the Brunton burn butane/propane? And as a side note, has anyone ever
been up to Hokkaido and knows about the availability of white gas or
butane/propane canisters? Thanks...
Jeromy Miceli
Volker Hetzer
> I'm going to be out in the country for awhile (Hokkaido, Japan, whooo!)
> and I've narrowed my camp stove choices to two, the Brunton Nova
> Optimus Multifuel Pack Stove ( http://www.brunton.com/product.php?id=60
> ) and the Coleman Fyrestorm SS (
> http://www.coleman.com/coleman/colemancom/detail.asp?product_id=9775-A25&categoryid=2005
> ). Anyone have any experience with either of these?
It worked, but you had to take it apart and clean it every time you wanted
to use it. Maybe it was something in the kerosene, I don't know.
My advice is, figure out what fuel you can get and buy accordingly.
IMHO you can get gasoline everywhere you have cars, so I would go for a
robust gasoline stove, one that is rated for car gasoline and not just
that specially cleaned stuff.
I would not use propane/butane because I don't like pressurized things
on my trails and if they depressurize for some reason they are harder to
replace in the countryside.
Lots of Greetings!
Volker
--
For email replies, please substitute the obvious.
Josh Assing
My MSR expidition works awesome no matter where I go; or what I shove thru it.
I recently was gifted a dragonfly -- nice stove for weekend/car camping -- the
easy simmering is nic e-- it's a multifuel stove; but I havent' tested it at
altitude.
The whisperlight international is a great stove -- the expidition (XKG) is LOUD!
Jet-engine loud; but has never failed me....
Why have you ruled out the MSR multifueled stoves?
--- AntiSpam/harvest ---
Remove X's to send email to me.
Clyde
> I've used both and sold them for $5 at a garage sale after a few uses.
Not likely, the Coleman has only been on the market for a month or so.
The Fyrestorm is superb as a cartridge stove since cold is a non-issue
and it really cranks the heat. Rather mediocre for use with gas due to
fiddle factor. But if you have butane/propane, it's probably the best
expedition stove available now. Overkill if cold weather isn't an issue.
Construction of the Optimus beats MSR handsdown but IMHO Primus has the
edge for liquid fuel stoves.
John Decker
jero...@gmail.com says...
This brief initial examination (URL below) confirms what I had initially
though about the Fyrestorm---Its not ready for Prime-Time!!
Apparently it was simply rushed into production with limited innovation and
fine tuning. In my opinion, the Fyrestorm is a hodgepodge of
loose components seeking unity. Apparently, even with the use of Titanium
metal, its total weight (REI advertisement URL below) is heavy and the boil
time, based on the initial review below, using Coleman fuel is no better than
some alcohol stoves under similar
outdoor conditions. I have not seen a review of the Coleman Fyrestorm stove by
Backpacker Magazine and now I can see why. I give it an overall
stove rating of 2 burners out of 6 burners. Backpacker Magazine gives
perspective stoves an objective real world evaluation.
Note REI's advertisement of the Fyrestorm. There was simply NO independent
evaluation
of this stove!! Most of the information seems to have originated from Coleman.
Also of interest, is the fact that the Powermax Fuel Adapter is still
unavailable for common canisters use on the Coleman exponent Xtreme stove. The
advertisment states the adapter will be ready by "spring 2006". It believe that
spring has passed, however.
I believe that the two new/improved Optimus stoves from Sweden
will be the hot items for the discerning technophile trekker with deep pockets
and
a preference for small stoves...
1) Optimus Nova + is a true multi-liquid fuel stove. MSRP: $205.77. This stove
has a new single burner control valve located on the fuel line near the fuel
pump that eliminates a control valve on the stove itself and allows simmering of
delicate meals. The fuel line control valve is an innovative idea if it works as
advertised. This newer model should also be more compact when put away in a
backpack sans the flip-down protruding stove burner control.
http://www.outdoorgb.com/p/optimus_nova_plus_lightweight_compact_stove/
2) Optimus Stella component LP-gas canister stove. MSRP: $110.80. This baby is
advertised as a thin compact stove that folds to 35mm for easy storage with
piezo igniter located on the canister fuel control valve. A long insulated
covered wire appears to wrap around the hose to carry the electric current from
the piezo igniter to the gas burner and ignite the LP gas.
The insulated electrical wire that carries the current is really not a new idea
however. An older Primus Spider stove (ca. late 1980's) used this
wrapped-wire-around-hose technique to transmit electic current from Piezo
igniter located on the gas control valve to the stove burner. The piezo worked
haphazardly in the old Primus spider stove and it was recommended by many users
to carry either a cigarette lighter or matches as a backup precaution. I know
the piezo malfunction problem to be a fact because I owned one of the old Primus
spider stoves and used it in Colorado at 12,000ft in 1989. Hopefully, this new
piezo igniter has been improved?
http://www.outdoorgb.com/p/optimus_stella_plus_lightweight_compact_stove/
Eugene Miya
<jero...@gmail.com> wrote:
>the Brunton burn butane/propane? And as a side note, has anyone ever
>been up to Hokkaido and knows about the availability of white gas or
>butane/propane canisters? Thanks...
Troll over in soc.culture.japan.
--
--------------
gigapower wg pump?
"John Decker" <John_...@newsguy.com> wrote in message
news:e6ajf...@drn.newsguy.com...
the Moderator
<jero...@gmail.com> wrote in message
news:1149785869.7...@y43g2000cwc.googlegroups.com...
I have the Brunton Optimus nova. It is loud and does not get very hot.
the Moderator
"Clyde" <y...@figureitout.com> wrote in message
news:1hgmki6.1oxcv1f1le3e4tN%y...@figureitout.com...
They don't compare in performance. MSR Whisperlight is much hotter and I
don't think the construction of the Optimus is all that great. They both
weigh about the same.
Bill Tuthill
>>
>> > I've used both and sold them for $5 at a garage sale after a few uses.
>>
>> Not likely, the Coleman has only been on the market for a month or so.
>> The Fyrestorm is superb as a cartridge stove since cold is a non-issue
>> and it really cranks the heat. Rather mediocre for use with gas due to
>> fiddle factor. But if you have butane/propane, it's probably the best
>> expedition stove available now. Overkill if cold weather isn't an issue.
>>
>> Construction of the Optimus beats MSR handsdown but IMHO Primus has the
>> edge for liquid fuel stoves.
>
> They don't compare in performance. MSR Whisperlight is much hotter and I
> don't think the construction of the Optimus is all that great. They both
> weigh about the same.
Interesting reports. Seems that price has no bearing on performance.
I'm really enjoying my Primus Yellowstone Classic, which cost only $26.
It accepts standard butane/propane canisters, and seems hotter than the
huge Century one-burner stove sitting on heavy Coleman propane canister.
Not the lightest stove in the backpacking universe, but the flame radius
is as large as my stove at home.
Chris Townsend
Moderator <sparky@no_spam_engineer.com> writes
well and has proved durable. With multi-fuel and white gas stoves I've
found that different models of the same stove can vary in performance.
The Nova has just been revised. I haven't tested the new version yet.
John Red-Horse
>
>I recently was gifted a dragonfly -- nice stove for weekend/car camping -- the
>easy simmering is nic e-- it's a multifuel stove; but I havent' tested it at
>altitude.
>
I have, and it works great at altitude. I think that the Dragonfly, while
not the lightest horse in the barn, is an extremely versatile stove. I
generally use it only for winter camping, though.
cheers,
john
David
In my opinion, the Fyrestorm . . . using Coleman fuel is no better than
some alcohol stoves under similar outdoor conditions.
evaluation.
http://tinyurl.com/om7qv
David n...@mindspring.com
I'm a Primus OmniFuel stove user who is interested in how it compares to the
Coleman Fyrestorm and the (Brunton) Optimus Nova. Here are my thoughts:
BOILING TIMES
First, I want to clarify that the "real world evaluation" at John's tinyurl
link above is at http://BackpackGearTest.Org and not at Backpacker Magazine.
The person evaluating the stove, Rick Dreher, wrote that the Fyrestorm took
5 minutes and 5 seconds to boil a liter (33.81 ounces, or 1.05 quarts) of
water using a butane/propane canister as a fuel source and 5 minutes and 5
minutes and 33 seconds to boil a liter of water using white gas (i.e.,
Coleman fuel, a form of unleaded gasoline).
He prefaced these results by saying that "With white gas or automotive gas,
Coleman rates the Fyrestorm at a maximum output of 10k BTU and 75 minutes
burn time using the supplied bottle (I'm presuming these times are based on
maximum output with a full bottle). With canister fuel, Coleman rates output
at 14k BTU and a 45-minute burn time, presumably with a Coleman 220 g (7.8
oz) canister, running at full blowtorch."
However, his test results for the Fyrestorm's boiling times have to be
discounted in view of Dreher's conclusion that "It's clear that canister
mode uses significantly less fuel and can heat water moderately faster
(probably a lot faster if I'd let it run wild)." In other words, he was not
using the Fyrestorm at maximum power.
By comparison, Coleman's Fyrestorm Webpage http://tinyurl.com/b8uu8 claims
these boiling times:
10,000 BTU's using white gas: Boiling time: 3.5 minutes (1 liter?)
14,000 BTU's using butane/propane canister: Boiling time: 3.2 minutes (1
liter?)
In a comparison of boiling times of various white gas and butane/propane
canister stoves on page 282 of Chris Townsend's "The Backpacker's Handbook"
(McGraw-Hill, 3rd edition, 2005) http://www.auchnarrow.demon.co.uk, the
Primus OmniFuel boiled a pint (0.47 liters, 0.5 quarts) of water in 2
minutes using a butane/propane canister, and in 8 minutes, 10 seconds using
Coleman fuel (white gas). By comparison, the Optimus Nova took only 4
minutes, 4 seconds using Coleman fuel.
The pewter color plastic tag which was attached to my Primus OmniFuel states
that the stove works with white gas and kerosene and a "propane/butane mix"
at "180g/h" " /8000/BTU/hr." with "Valve #: 51907." Based upon this
information, one could reasonably conclude that the Coleman Fryestorm with a
significantly higher BTU output should boil water faster than the Primus
OmniFuel. However, there might be other factors, which might affect boiling
times, such as the diameter of the flame.
STOVE WEIGHT
I weighed the Primus OmniFuel on a supermarket digital scale. Here are the
results:
The stove by itself: 408 grams, 14.4 ounces
The all metal liquid pump (not the current plastic & metal Primus ErgoPump):
131. 5 grams, 4.64 ounces
By comparison, the Coleman Fyrestorm only weighs 215 grams, 7.6 ounces.
And its pump only weighs 74 grams, 2.8 ounces.
(Source: http://tinyurl.com/om7qv)
However, in order to use the Coleman Fyrestorm with a butane/propane
canister, you must add 85 grams (3 ounces) for the canister stand, a
component which is not used with the Primus OmniFuel.
The advantage of using the canister stand with the Fyrestorm is that
supports an inverted canister, so that the butane/propane gas is drawn out
in liquid form, so that all of the contents can be used in subfreezing
weather. There is no need to substitute an isobutane fuel mix or use
external chemical warmer packs to ensure fuel flow.
The canister connected to the Primus OmniFuel could also "probably" be
slowly tilted after the stove is lit to obtain a similar performance
benefit. Be aware, however, that if you try this with other canister stoves
which do not have a pre-heat tube in the burner (or equivalent), that you
could risk turning your stove into a liquid fuel flame thrower and killing
or injuring yourself and burning down the forest.
There is also a titanium version of the Primus OmniFuel. However, the
weight savings are very modest and the cost is more than twice the standard
aluminum and stainless steel version of the OmniFuel.
For more information, see:
New Primus TITANIUM OmniFuel stove
rec.backcountry circa May 8, 2005
http://tinyurl.com/zgsyv
FUEL BOTTLE
The Primus OmniFuel can be attached to most, but not all, other metal liquid
fuel bottles. In contrast, the Coleman Fyrestorm only comes with one size
fuel bottle. Coleman warns not to use any other fuel bottle. Be aware that
there can be subtle, but critical differences in the bevel of the lip and
threads at the openings in fuel bottles which may affect safety. Fuel
bottles can be pressurized up to hundreds of pounds of pressure per square
inch.
Here's a comparison between the Coleman fuel bottle which works with the
Fyrestorm and the new Primus 1.5 liter fuel bottle:
Fyrestorm fuel bottle 0.65 liters, 22 ounces
Net capacity 0.473 liters, 16 ounces
Empty weight: 108 grams, 3.8 ounces
http://tinyurl.com/k93wu
Primus no. 732530 "1.5 [liter] Fuel Bottle" (lacquered inside to provide the
bottle with better protection)
Net capacity (?) 1.335 liters, 45.14 ounces
212 grams, 7.5 ounces
http://tinyurl.com/opdck
OTHER SOURCES OF INFORMATION
Here's some other sources of information which should be of interest to you:
New Coleman Backpacking Stove--Fyrestorm
rec.backcountry
http://tinyurl.com/ruqml circa February 10, 2006
Primus OmniFuel 328984 canister compatibility - also applies to Fyrestorm
rec.backcountry
http://tinyurl.com/kpvnr circa July 26, 2002
http://tinyurl.com/f6phv circa April 29, 2005
Fyrestorm Manual
http://www.coleman.com/coleman/images/pdf/9770_5-A25.pdf
For Norwegian readers - comparison of Primus OmniFuel & Karrimor Fleixifuel
stoves (and Optimus Nova) - Primus wins!
rec.backcountry circa April 28, 2005
http://tinyurl.com/jd2ry
CONCLUSION
The Coleman Fyrestorm offers significant weight savings over the Primus
OmniFuel. It also does away with conventional priming, but requires the
liquid fuels user to follow the ignition procedure with exactitude. On the
down side, it cannot burn Jet-A, kerosene and diesel, as the Primus can.
But using these fuels is problematic, as they burn dirty ands sooty and
require the user to do frequent cleaning and maintenance of the burner and
or fuel line.
If the boil times at maximum power are as good, or better than the Primus, I
would say for most users theFyrestorm stove would appear to be a better
choice.
In comparison to the Optimus Nova, which can only use liquid fuels, I would
strongly recommend getting a stove which allows the user to chose between
using a butane/propane canister or liquid fuel. Generally speaking,
canisters are simpler, safer and more user friendly.
To find Snowpeak dealers in Japan who probably can sell you fuel, click on
http://tinyurl.com/k9noz
Clyde
> By comparison, the Coleman Fyrestorm only weighs 215 grams, 7.6 ounces.
> And its pump only weighs 74 grams, 2.8 ounces.
That's the weight for the Ti stove, the SS version is 2 oz. more and $40
less.
The pump/priming is so bad that the Fyrestorm should not be considered a
white gas stove except in emergencies (definitely not compatible with
Sigg/MSR bottles btw). With butane blends, it has no equal in cold
weather -- way better than any liquid-fueled stove. Too bulky and heavy
for above freezing though; it works but there are better options.
Forget trying to compare boil times from different sources. Absolute
waste of time.
Pity no company has ever made a good hanging stove system, damned
lawyers.
David
With butane blends, it [Fyrestorm] has no equal in cold
weather -- way better than any liquid-fueled stove.
David n...@NOSPAMmindspring.com
I would think that most other butane stoves which preheat (vaporize) their
fuel could equal the Fyrestorm, if the user carefully inverted the fuel
cartridge to avoid the problem of diminished vapor pressure in the canister
due to the cold. See the explanation below:
Source: A thread at Backpackinglight.com's public access reader forums at
http://tinyurl.com/ph9ya
From: Douglas Frick
Subject: Remote canister liquid-fed butane stoves
Date: 02/12/2005 22:28:45 MST
On Backpacker.com http://tinyurl.com/eurym a reviewer of the Primus
MultiFuel [the predecessor of the OmniFuel] stove mentioned "...with
canisters the long tube and its swiveling head provide the great convenience
of letting you prop the canister upside down while extracting the last drop
of fuel," however I'm not sure this implies they've actually run it that
way. (Anybody willing to try it?)
* * *
From: Douglas Frick
Subject: remote canister liquid-fed butane stoves
Date: 02/17/2005 22:57:26 MST
I wrote:
>So, any other liquid-fed butane stoves out there besides the Coleman?
Thanks to Jason Shaffer for his list of remote canister liquid-fed
butane/propane stoves with vaporizer tubes. In answer to my question about
whether these other stoves can run liquid-fed, I found the following on the
Zen Stove site about turning remote canisters upside-down to make them
liquid-fed:
http://home.comcast.net/~agmann/stove/Canister.htm
"With some setups, canisters may be used upside down. This would force out
liquid instead of gas into your fuel line, similar to running PowerMax
canisters. The Primus Himalaya manual states that one safe cold environment
trick is to:
"Turn down the control valve as low as possible. Now hold the gas cartridge
and turn it upside down slowly and very carefully. While doing so, you must
never lift the cartridge higher than the stove itself to avoid a sudden
burst of flames."
When asked via email if the MSR Windpro could operate with the canister
upside down, a tech at MSR replied:
"Yes, you can turn the canister upside down when using the WindPro but you
would want to use the same precautions stated in the Primus manual."
Since the Primus Himalaya EasyFuel, MSR WindPro, MSR Rapidfire, and Snowpeak
GigaPower BF Stove [GS-300A] have similar designs with a hose connection and
heated vaporizer tube, they should be able to run PowerMax canisters (you
may need an adapter) or regular fuel canisters upside down - do so at your
own risk.
There are several remote fueled canister stoves, such as the Markill Spider,
that don't have vaporizer tubes (generators). This feature is desirable to
vaporize the fuel prior to it exiting the jet. Running a canister upside
down without a vaporizer tube isn't recommended and can be dangerous
-----------------------------------------------
ERRATUM: Here is the corrected link to the Coleman 22 ounce fuel bottle:
http://tinyurl.com/9tyh9
David
I have used the optimus nova in Nepal. Can't say I was very impressed.
It worked, but you had to take it apart and clean it every time you wanted
to use it. Maybe it was something in the kerosene, I don't know.
David n...@NOSPAMmindspring.com
Kerosene is not as clean burning as white gas. However, in a place like
Nepal, there very well may have been contaminants in the fuel. For this
reason, I suggest using the washable Coleman CorrectStop fuel filter funnel,
which filters both dirt and water and prevents you from overfilling your
fuel bottle. It may be best backpacking fuel filter ever made. It was
discontinued several years ago, but it may be in stock from a number of
sources. Read more about it at: http://tinyurl.com/fk7xk
Clyde
> I would think that most other butane stoves which preheat (vaporize) their
> fuel could equal the Fyrestorm, if the user carefully inverted the fuel
> cartridge to avoid the problem of diminished vapor pressure in the canister
> due to the cold.
Of course none of those are designed to hold an inverted cartridge so
you have to jury rig them. The screw-on adaptor for Powermax stoves puts
them in contention but is bulkier and heavier (they're decent stoves
alone if you can find the PM fuel).
David
Of course none of those are designed to hold an inverted cartridge so you
have to jury rig them.
David n...@NOSPAMmindspring.com
Here's more information from
http://www.bushwalking.org.au/FAQ/FAQ_GasStoves.htm
You can turn many remote cartridge stoves into liquid feed stoves. The Snow
Peak GS-200D (at one stage selling for a horrendous AU$320) has a preheat
tube and is shown on the cover of its box with a standard screw-thread or
"Epigas" cartridges placed upright. The manufacturer does not recommend you
tip the cartridge upside down to get a liquid feed, but it has been shown to
work quite well. The MSR WindPro stove is similar but lighter, and also
works just fine with the canister inverted. Some of the Primus Himalaya
series (eg Omnifuel) also have a preheat tube, and could do the same. I
gather that Primus does actually mention this possibility, although they
advise great care in tipping the cartridge upside down. The Primus ones
aren't cheap either.
How do you tip a cartridge upside down in a stable manner is of course a
good question. One method which the author has used is to fit the cartridge
with some Lexan legs, as shown to the right. The weight of the three legs
plus the rubber bands is about 20 grams: hardly significant. The
configuration is quite stable, by the way.
Why does the liquid feed idea work so well? There are two reasons. The mix
forced up the tube is just that: the full mixture of butane and propane. And
there is no variation in the mix because there is no evaporation inside the
tank - for details see the page on gas Mixtures and Solutions. It's a liquid
hydrocarbon fuel just like petrol or kero, and it behaves just like kero or
petrol. The only real difference is that it boils at a somewhat lower
temperature than petrol or kero. The curious thing is that, while valving
liquid kero or petrol can be tricky, the liquid feed gas stoves seem to
manage to valve the liquid gas fairly well. Anyhow, all the liquid feed
stoves mentioned simmer very nicely, although any adjustment has a small
delay time.
Is there any danger in using a liquid feed on a gas stove? It is hard to see
why there should be if the stove has a preheat tube. The liquid fuel will
reach the preheat section and vaporise with the heat from the flame (if it
hasn't vaporised earlier). The jet hole, which is typically of the order of
0.3 mm diameter, will only let a certain amount of gas through at a time.
The back pressure will simply limit the amount of fuel reaching the preheat
section. This is exactly the same as for petrol and kero stoves: exactly.
Just make sure you have a flame at the burner before you turn on the valve,
and do that gently at the start. However, do not try this if the stove does
not have a preheat tube, and the author accepts NO responsibility for what
you do!
John Decker
>
>"John Decker" <John_...@newsguy.com> wrote
>In my opinion, the Fyrestorm . . . using Coleman fuel is no better than
>some alcohol stoves under similar outdoor conditions.
>Backpacker Magazine gives perspective stoves an objective real world
>evaluation.
>http://tinyurl.com/om7qv
>
>David n...@mindspring.com
>I'm a Primus OmniFuel stove user who is interested in how it compares to the
>Coleman Fyrestorm and the (Brunton) Optimus Nova. Here are my thoughts:
>
>BOILING TIMES
>
>First, I want to clarify that the "real world evaluation" at John's tinyurl
>link above is at http://BackpackGearTest.Org and not at Backpacker Magazine.
>The person evaluating the stove, Rick Dreher, wrote that the Fyrestorm took
>5 minutes and 5 seconds to boil a liter (33.81 ounces, or 1.05 quarts) of
>water using a butane/propane canister as a fuel source and 5 minutes and 5
>minutes and 33 seconds to boil a liter of water using white gas (i.e.,
>Coleman fuel, a form of unleaded gasoline).
<snip>
First, let me state that no clarification is needed on what I said. You have
purposely omitted most of the paragraph above with ellipsis marks. The URL that
I used is obviously not Backpacker magazine and I never said that it was. You
have misrepresented what I had said.
Secondly, I clearly stated that an initial review was involved in the
URL:http://tinyurl.com/om7qv , again I never stated the stove review was
conducted by Backpacker Magazine. Although I eagerly awaited a spring review of
the Fyrestorm stove by Backpacker Magazine, which never materialized.
Furthermore, the Original Poster's question about stoves was a comparison of the
Coleman Fyrestorm and Optimus Nova stove. Your analysis is a convoluted non
sequitur since it is based on another stove (Primus OmniFuel stove) which you
arbitrarily introduced in your analysis to compare it with the Coleman Fyrestorm
stove.
However, you can not in good faith compare the Coleman Fyrestorm stove to the
Omnifuel stove because the Omnifuel is not specifically designed to run on an
inverted gas canister. As you point out below, there is the probability of using
an inverted canister with the Omnifuel but it could have inherent dangers for an
inexperienced individual.
The quote from Chris Townsend's "The Backpacker's Handbook" is interesting:
"the Primus OmniFuel boiled a pint (0.47 liters, 0.5 quarts) of water in 2
minutes using a butane/propane canister, and in 8 minutes, 10 seconds using
Coleman fuel (white gas). By comparison, the Optimus Nova took only 4 minutes, 4
seconds using Coleman fuel. "
The Optimus Nova results looks good to me with liquid fuel boil time of 4 min-4
sec, vs. Omnifuel 8min-10sec for 0.47 Liters. The Fyrestorm stove's reported
boil time by Coleman is 3.5 minues for 1 liter? The Fyrestorm's 34 second boil
time lead is insignificant. Based on Rick Dreher's preliminary evaluation of the
Fyrestorm stove, I believe that the boil time it is going to be closer to 5
minutes at ambient temperature with altitude taken into consideration for 1
Liter of water. I will look forward to Mr. Townsend's future test results and
commentary for the Coleman Fyrestorm stove.
Several important points to be made about these stoves.
1)The Coleman Fyrestorm requires excess pumping to maintain a stable flame
during start-up. This is contrary to other manually primed stoves and takes some
getting use to.
2) Coleman does not recommend using Canadian unleaded gasoline in the Fyrestorm
stove. Therefore, not all unleaded petrol can be used in this stove.
3) The Optimus Nova has a stable track record compared to the new Fyrestorm
stove. If the OP buyes the Fyrestorm stove, he should pack along a repair kit
with a wrench to throughly clean the stove.
4) In most foreign countries, the likelihood of finding liquid fuel is better
than finding LP-canisters. Japan may be different, I do not know.
5) You mentioned that the Fyrestorm stove did not need priming. This is not
correct. The Fyrestorm's automatic priming sequence primes the stove with a
yellow flame ( especially in freezing weather) that eventually settles down to a
normal blue flame. This is not unlike manual priming of the Optimus Nova.
6) Your weight comparison of the Primus Omnifuel to the Fyrestorm is
insignificant. The Omnifuel weighted 14.4 oz compared to the Fyrestorm weight of
13.3oz. The Optimus Nova weighs 14.8oz. So does weight really matter in this
comparison?
Your stove comparison and conclusion is replete with assumptions based largely
on uncorroborated facts from the Coleman company's tests. What is sorely needed,
for the public consumer, however, is an independent impartial test by a group
such as Backpacker Magazine or even Consumer Reports.
To be completely impartial in any stove test the stove should be purchased off
the shelf from a random store that sells trekking stoves. Stoves directly
submitted by stove companies to testing groups or individuals should not be
accepted because those stoves may not be a representative sample of what the
public buys.
JD
David
6) Your weight comparison of the Primus Omnifuel to the Fyrestorm is
insignificant. The Omnifuel weighted 14.4 oz compared to the Fyrestorm
weight of
13.3oz. The Optimus Nova weighs 14.8oz.
David n...@NOSPAMmindspring.com
John, it must be pointed out that the Titanium Fyrestorm is significantly
lighter:
Coleman Titanium Fyrestorm
Burner = 7.6 oz.
Butane/propane gas mix canister stand = 3.0 oz.
Liquid fuel pump = 2.8 oz.
BTW, John, have you used the Fyrestorm?
Clyde
> 2) Coleman does not recommend using Canadian unleaded gasoline in the
> Fyrestorm stove. Therefore, not all unleaded petrol can be used in this
> stove.
That's because the Canooks use MMT in their gas and it's banned by the
EPA in the US. IOW the stove will work but the manganese fumes may hurt
you, same as with any other stove. Just use butane and be happy.
> 3) The Optimus Nova has a stable track record compared to the new Fyrestorm
> stove. If the OP buyes the Fyrestorm stove, he should pack along a repair kit
> with a wrench to throughly clean the stove.
Fyrestorm comes with all the spare parts. The MSR XGK EX and the
replacement for the Nova coming next year don't/won't have a stable
track record, so what?
> 4) In most foreign countries, the likelihood of finding liquid fuel is better
> than finding LP-canisters. Japan may be different, I do not know.
You mean most foreign countries besides Canada, Mexico, all of Europe,
Iceland, Peru, Argentina, New Zealand, Japan, Nepal, Pakistan....
Screw-in butane is very common at any gateway town these days.
> or even Consumer Reports.
Lawd help us. Maybe Coleman will buy a few full page ads and earn a
Backpacker editor's choice award.
> To be completely impartial in any stove test the stove should be purchased off
> the shelf from a random store that sells trekking stoves. Stoves directly
> submitted by stove companies to testing groups or individuals should not be
> accepted because those stoves may not be a representative sample of what the
> public buys.
Hogwash. Total waste of time and money.
David
That's because the Canooks use MMT in their gas and it's banned by the
EPA in the US. IOW the stove will work but the manganese fumes may hurt
you, same as with any other stove. Just use butane and be happy.
David n...@NOSPAMmindspring.com
The Coleman Fyrestrom manual does not mention the hazard of fumes from
Canadian gasoline containing manganese. Instead, it warns about Canadian
gasoline which "contain[s] manganese compounds that are unacceptable to both
generator performance and reliability"
http://www.coleman.com/coleman/images/pdf/9770_5-A25.pdf
I have also read similar warnings at the Coleman Website and Coleman stove
manuals not to use Canadian gasoline containing manganese in other Coleman
stoves because it could corrode, for example, the fuel tank and other parts.
MB
> With butane blends, it has no equal in cold weather -- way better
> than any liquid-fueled stove.
?! Please elaborate.
I thought it was common knowledge that gaseous fuel stoves
don't work well at very cold temperatures, although 'cold-weather'
blends help somewhat, as do some cartidge heating solutions.
Hence liquid (or solid) fuel stoves have (afaik) always been the
way to go in cold weather conditions. Is Fyrestorm really a
revolutional design that would change all this?
Moreover, some of the marketing of gaseous-fuel stoves has
been badly misleading, quoting 'expedition' usage in extreme
high-altitude environments - Everest and the like - to impress
the naive consumer. Of course, high-altitude conditions are
exceptionally bening for a gaseous fuel stove in cold conditons;
the real test is at the sea level.
MB
> > 4) In most foreign countries, the likelihood of finding liquid
> > fuel is better than finding LP-canisters. Japan may be different,
> > I do not know.
Clyde >
> You mean most foreign countries besides Canada, Mexico, all of Europe,
> Iceland, Peru, Argentina, New Zealand, Japan, Nepal, Pakistan....
> Screw-in butane is very common at any gateway town these days.
I'm probably nitpicking, but Iceland *is* a part of Europe. And so
is, eg, Russia, which is area and backcountrywise by far the
largest country in Europe.
When travelling to Russian backcountry, I wouldn't want to rely on
finding unleaded gasoline for the car. Hence an old car accepting
leaded low-octane gas is a better idea, or, better still, a diesel
vehicle. But even diesel fuel can sometimes be hard enough to find.
In contrast, assuming that LP-canisters could be readily found seems
simply absurd.
Clyde
> I thought it was common knowledge that gaseous fuel stoves
> don't work well at very cold temperatures, although 'cold-weather'
> blends help somewhat, as do some cartidge heating solutions.
> Hence liquid (or solid) fuel stoves have (afaik) always been the
> way to go in cold weather conditions. Is Fyrestorm really a
> revolutional design that would change all this?
Nah, Coleman has offered liquid-feed butane stoves for years now (X
models) but finding their fuel wasn't easy. The Fyrestorm is just a
refinement of the concept that takes widely available fuel. No gas
involved until the burner head so cold isn't a factor even at low
altitude (also the propane doesn't burn off first). Think of it as a
very hot kerosene stove that you never pump with self-contained fuel
that doesn't clog or leak inside your pack.
Clyde
> In contrast, assuming that LP-canisters could be readily found seems
> simply absurd.
For the popular destinations, it's a sure thing nowadays. The OP wasn't
referring to the European attractions of Siberia or the Kamchatka
peninsula.
John Decker
What is the weight of the fuel bottle? I was not sure if you were referring to
the Ti or SS model in your weigth comparison. No, I have not used the Fyrestorm;
have you? I do, however, use the Coleman Xtreme which, in my opinion, is the
best LP stove that Coleman produces. The Powermax fuel canisters, as you know,
are very difficult to find. I am awaiting the canister adapter to be on sale for
the Xtreme stove. Perhaps this adapter will solve the canister problem.
JD
David
John, it must be pointed out that the Titanium Fyrestorm is significantly
"John Decker" John_...@newsguy.com
What is the weight of the fuel bottle?
I was not sure if you were referring to the Ti or SS model in your weigth
comparison.
No, I have not used the Fyrestorm; have you?
David n...@NOSPAMmindspring.com
1) John, according to the information at the "tinyurl" link you posted in
this thread, the fuel bottle weighs 3.8 oz (108 grams). BTW, with respect
to your earlier post wrongfully alleging that I "misrepresented" what you
wrote concerning this "tinyurl" link, I neither misrepresented or
represented anything you said. Instead, I merely clarified for the reader
that the "tinyurl" link was to http://backpackinglight.com.
2) As clearly stated above, I was referring to the Titanium Fyrestorm.
3) I have not used the Fyrestorm.
David
news:ZEBjg.12509$921....@newsread4.news.pas.earthlink.net...
BTW, with respect to your earlier post wrongfully alleging that I
"misrepresented" what you wrote concerning this "tinyurl" link, I neither
misrepresented or represented anything you said. Instead, I merely
clarified for the reader that the "tinyurl" link was to
http://backpackinglight.com.
Correction: meant to say http://BackpackGearTest.Org
Eugene Miya
>Clyde >
>> You mean most foreign countries besides Canada, Mexico, all of Europe,
>> Iceland, Peru, Argentina, New Zealand, Japan, Nepal, Pakistan....
>
Did Iceland make it into the EU?
>is, eg, Russia, which is area and backcountrywise by far the
>largest country in Europe.
I doubt that Clyde's enumeration excluded Iceland from Europe.
--
sig...@binet.is
Eugene Miya wrote:
> In article <7uvpshd...@hess01.research.nokia.com>, MB <*@*.*> wrote:
> >Clyde >
> >> You mean most foreign countries besides Canada, Mexico, all of Europe,
> >> Iceland, Peru, Argentina, New Zealand, Japan, Nepal, Pakistan....
> >
> >I'm probably nitpicking, but Iceland *is* a part of Europe. And so
>
> Did Iceland make it into the EU?
Europe and the EU is not the same thing, Iceland has decided to stay
outside the EU but the EU has made it clear that Iceland can join at
any time so it is not a case of Iceland not "making it into the EU".
David
The pump/priming is so bad that the Fyrestorm should not be considered a
white gas stove except in emergencies (definitely not compatible with
Sigg/MSR bottles btw).
David n...@mindspring.com
Is your comment above based on Rick Dreher's initial report at
BackpackGearTest.org @ http://tinyurl.com/om7qv. (Excerpts from Rick's
report appears below). Or a different source of information?
Rick's report:
White gas setup begins with filling the bottle about 2/3ds full, inserting
and screwing in the pump assembly and pumping roughly forty times, while
covering the pump knob's air hole with a finger. After attaching the burner
by screwing in the threaded hose connector, the burner legs are opened and
the burner placed atop the reflector disc. Next, the burner's adjuster valve
is fully opened (important!), the pump fuel valve is opened and the burner
lighted. The initial flame will be yellow and tall but once vaporization is
achieved and the stove has settled down to a steady blue cooking flame,
output can be adjusted using the adjuster valve. The instructions suggest
increasing fuel pressure at this point with more pumping
White gas mode is the touchier of the two, especially at startup. Beyond the
obvious filling and pumping, tweaking is required to achieve a steady
cooking flame. I found it tricky to sustain the startup flame without fuel
spilling down the burner assembly and pooling underneath (keeping the area
clear of flammable debris is critically important).
White gas startup requires strict adherence to the following technique.
Whenever I stray from the formula I get a very high and sooty yellow flame,
with liquid fuel spilling down onto the ground. In a nutshell:
· Fill the bottle only to the fill line (16 fl oz/473
ml, about two-thirds full).
· Pump forty strokes. (Can't remember that count? Think
Lizzie Borden.)
· Open and close the adjuster valve a few times to clean
the jet then leave it FULLY OPEN.
· Open the fuel valve and light the burner.
· When the initial yellow flame turns blue, pump the
bottle an additional twenty to forty times.
Overfilling or over-pumping the bottle will create the giant yellow flame.
Under-pumping will create the giant yellow flame. Not cleaning the jet or
setting the flame adjuster valve to anything else than wide open will create
the giant yellow flame. Because one does not want the giant yellow flame,
following these directions to the letter is the key to a cooking flame in
less than a minute.
Once warmed up and vaporizing well, the white-gas mode Fyrestorm is a steady
performer, happily chugging along in a manner familiar to white gas stove
users. Intermittent pumping while cooking maintains the flame as gas is
used, and fine adjustment at the burner is instantaneous. Damping the flame
down to a simmer is simple because the adjuster can't inadvertently shut the
stove off.
Unexpected fuel loss. I've found it's possible to lose an entire bottle of
white gas when pressurized fuel leaks past the main fuel valve and out, onto
the ground. I've had this happen twice now, and make a point of cranking
down the valve quite a bit when closing it. I've also taken to bleeding off
the pressure when stowing the bottle, unscrewing the cap until it's
released. Note that an unpressurized bottle will still develop a good amount
of pressure sitting in the sun.
In either fuel mode, the fuel valve functions as an on/off switch while the
flame adjuster does just that-adjusts the flame from low to high. Flame
response to the adjuster is instantaneous, with none of the time delay and
"tweakiness" familiar to remote stoves with a single valve. Because the
flame adjuster doesn't have an "off" position a low, simmer flame can be
achieved without inadvertently shutting the stove off, and the wide burner
provides heat across a broad area, better for cooking. There is a
significant time delay when shutting the stove down, as fuel in the hose is
spent. I find it best to open up the flame adjuster to help the shutdown
process along. The stove is a quiet performer too, a relief to anybody
accustomed to the roar of burner-plate type white gas stoves.
Clyde
J. Curl
>
> No gas
> involved until the burner head so cold isn't a factor even at low
> altitude (also the propane doesn't burn off first).
It's true that very little heat is required to drive the liquid fuel,
but there is still a temperature below which the canister pressure will
be zero, for a given altitude. I once put a new Snowpeak canister in my
freezer (about -5F) and the pressure was only 12 psig. Perhaps it falls
to zero at -20F?
David
I have a Ti.
David n...@mindspring.com
Have you timed boiling water using a canister with your Ti?
Clyde
> David n...@mindspring.com
> Have you timed boiling water using a canister with your Ti?
Yes, meaningless to post. Never compare different sources.
Clyde
> It's true that very little heat is required to drive the liquid fuel,
> but there is still a temperature below which the canister pressure will
> be zero, for a given altitude. I once put a new Snowpeak canister in my
> freezer (about -5F) and the pressure was only 12 psig. Perhaps it falls
> to zero at -20F?
No significant refrigeration effect when the fuel is inverted. Doesn't
take much pressure to push and there's a siphon.
David
with a canister to that of a Primus Omnifuel? Thank you.
MB
> Nah, Coleman has offered liquid-feed butane stoves for years now (X
> models) but finding their fuel wasn't easy.
Ah, now I see. So, these are liquid fuel stoves, with
liquid butane/propane, rather than petrol or alcohol that
liquid fuel stoves typically use. I'm obviously years behind
the cutting edge.
> Think of it as a very hot kerosene stove that you never pump
> with self-contained fuel that doesn't clog or leak inside your
> pack.
This sounds too good to be true ;). Coleman's marketing
claims are vague: "Unique liquid-withdrawal method for
threaded butane/propane canisters produces improved
performance in colder weather or high altitudes (vs. vapor
withdrawal)"
http://www.coleman.com/coleman/colemancom/detail.asp?product_id=9770-A25&categoryid=24752
Operation in cold weather *and* *low* altitude would be much
more telling about the winter performance. I'd like to see
a specification for the lowest operating temperature at sea
level, although I guess specifying a hard limit is rather
arbitrary.
So, does it actually work at, say, -40C at sea level? No
preheating? What about the siphoning Clyde mentioned... is
it needed, or will the cartidge pressure and gravity feed
suffice? How does the siphoning work?
MB
> > In contrast, assuming that LP-canisters could be readily found seems
> > simply absurd.
Clyde >
> For the popular destinations, it's a sure thing nowadays. The OP wasn't
> referring to the European attractions of Siberia or the Kamchatka
> peninsula.
Clyde is obviously teasing me... ;) There are however some
large wilderness areas still left in the European part of
Russia. Like the National Park of Yugud-Va. At some 12000
sq km, it is by far the biggest protected area in Europe, and
amongst the largest ones in the world. It's quite a bit larger
than eg Yellowstone.
Dunno about the "popular destinations" in Europe. I guess you
could order pizza and wine in those, so the LP-canisters are
perhaps not that critical <g>.
J. Curl
Right, but at some point there is no pressure. A siphon adds less than
half a psi per foot of height difference. If the fuel vapor pressure
drops signficantly below atmospheric pressure the stove will not
function.
Without knowing precisely what the fuel composition is it's impossible
to calculate where the failure temperature/elevation curve lies. If a
canister really contained a 20/80 mixture of propane/isobutane the sea
level failure temperature would be around -10F.
Clyde
> If a
> canister really contained a 20/80 mixture of propane/isobutane the sea
> level failure temperature would be around -10F.
Anytime it's below 0°F, smart people are cooking inside a tent (or
igloo, nod to Ed). Can't imagine any reason to stand around outside
melting snow and boiling water in extreme cold. Don't forget that with
the Fyrestorm, the canister is off to the side of the stove so it's
being warmed. The MSR Reactor takes a different approach but it won't be
out until next March (should be a great system).
John Decker
>
>John Decker <John_...@newsguy.com> wrote:
>
>> 2) Coleman does not recommend using Canadian unleaded gasoline in the
>> Fyrestorm stove. Therefore, not all unleaded petrol can be used in this
>> stove.
>
>That's because the Canooks use MMT in their gas and it's banned by the
>EPA in the US. IOW the stove will work but the manganese fumes may hurt
>you, same as with any other stove. Just use butane and be happy.
The manganese will over a period of time gum-up the stove. Coleman has said
nothing about its detriment to humans in its manual that I am aware of? Burning
butane will not be effective in extremely cold, low altitude environments.
Liquid fuel may have to be used sometime.
It's informative for the public to know that the Fyrestorm has problems with
this unleaded fuel. The Optimus Nova does not seem to have any undue problems
with this fuel nor does MSR stoves.
-------------------------
>> 3) The Optimus Nova has a stable track record compared to the new Fyrestorm
>> stove. If the OP buyes the Fyrestorm stove, he should pack along a repair kit
>> with a wrench to throughly clean the stove.
>
>Fyrestorm comes with all the spare parts. The MSR XGK EX and the
>replacement for the Nova coming next year don't/won't have a stable
>track record, so what?
Did I mention the new Nova Plus. No. I said "The Optimus Nova has a stable track
record compared to the 'new' Fyrestrom stove." You are interjecting extraneous
irrelevant information that avoids or convolutes any real reply.
---------------------------
>> 4) In most foreign countries, the likelihood of finding liquid fuel is better
>> than finding LP-canisters. Japan may be different, I do not know.
>
>You mean most foreign countries besides Canada, Mexico, all of Europe,
>Iceland, Peru, Argentina, New Zealand, Japan, Nepal, Pakistan....
>Screw-in butane is very common at any gateway town these days.
Gateway towns may have these LP canisters but many towns in the interior of
those countries do not have these canisters but do have petrol and kerosene. The
Fyrestorm, also, does not burn Kerosene which is used in some of the countries
(eg. Japan) that you have listed. The Optimus Nova (both old & new models) does
burn Kerosene, however. The Fyrestorm, more correctly, should not be called a
mult-fuel stove but rather a Tri-fuel stove---LP gas, unleaded auto gasoline,
White gasoline (Coleman type fuel).
----------------------------
>Lawd help us. Maybe Coleman will buy a few full page ads and earn a
>Backpacker editor's choice award.
Interesting comment Clyde. I did not realize, as you suggested, that the
Backpacker Editor's Choice Award may be based on stove companies advertisements
in its magazine?
---------------------------
>>To be completely impartial in any stove test the stove should be purchased off
>> the shelf from a random store that sells trekking stoves. Stoves directly
>> submitted by stove companies to testing groups or individuals should not be
>> accepted because those stoves may not be a representative sample of what the
>> public buys.
>
>Hogwash. Total waste of time and money.
Why do you say that Clyde? What criteria do you use in selecting a product that
you intend to purchase? Do you buy a product simply because of :Brand Name,
functionality innovation, or price? Some people that I know simply make a
decision based on price---If it cost more it must be better.
If you consider price and safety of all trekking stoves and their advertised
company statistics, some independent/impartial review becomes necessary for most
people who are considering the purchase of these stoves. Therefore I do not
consider it "Hogwash" nor a "total waste of time and money."
JD
Ed Huesers
>> If a
>> canister really contained a 20/80 mixture of propane/isobutane the sea
>> level failure temperature would be around -10F.
Clyde wrote:
> Anytime it's below 0°F, smart people are cooking inside a tent (or
> igloo, nod to Ed).
Heh, yeah. I get a charge out of the stove/fuel discussions
sometimes. I could pipe up often but that'd get rather tiring.
> Can't imagine any reason to stand around outside
> melting snow and boiling water in extreme cold.
It's good to have the experience so you know not to do it or how to
do it if required.
> Don't forget that with
> the Fyrestorm, the canister is off to the side of the stove so it's
> being warmed.
I haven't been following this thread real close but it would seem
that as soon as any liquid hit the hot generator there would be pressure
in the tank. The propane mix too... I've always heard that the propane
stoves stop working in MN households when it is -50f.
Does having a blend change the boiling temperature or does the
propane come off first at lower temps? From my experience with starting
a iso/butane stove for short periods and many times in the cold, the
propane seems to disappear.
But, like you said in other posts, our tests are usually flawed. I
found one problem on my stove a couple years ago. When I first tighten
the canister onto the stove, I get it tight, but with time and heat
[apparently] the metals grow and the canister needs to again be
tightened so the gas flows freely. That one problem pretty much makes
all my stove tests/conclusions moot.
> The MSR Reactor takes a different approach but it won't be
> out until next March (should be a great system).
Hmm...
Sure glad my Primus Mini Duo works great. I guess they don't make em
any more.
Ed Huesers
http://www.grandshelters.com
J. Curl
>
> Anytime it's below 0°F, smart people are cooking inside a tent (or
> igloo, nod to Ed).
True enough. But you have to admit that saying that "cold isn't a
factor even at low altitude" because smart people never let the fuel
get very cold is kind of an odd argument.
Ed Huesers wrote:
>
> Heh, yeah. I get a charge out of the stove/fuel discussions
> sometimes. I could pipe up often but that'd get rather tiring.
They're fun! Sometimes informative and usually a good geekfest.
> I haven't been following this thread real close but it would seem
> that as soon as any liquid hit the hot generator there would be pressure
> in the tank.
This makes no sense. Any line pressure caused by vaporization at the
generator would work against tank pressure.
> Does having a blend change the boiling temperature or does the
> propane come off first at lower temps? From my experience with starting
> a iso/butane stove for short periods and many times in the cold, the
> propane seems to disappear.
No fuel composition change with a liquid fuel stove.
David
anytime it's below 0°F, smart people are cooking inside a tent
David n...@NOSPAMmindspring.com
1) I thought the smart people knew enough NOT to cook inside a tent because
of the danger of carbon monoxide poisoning. And not to mention the danger
of a liquid fuel stove flare-up or the danger of fuel spilling on the floor
during priming. To illustrate this point, read what happened when Rick
Dreher used the Fyrestorm at http://tinyurl.com/om7qv. Imagine the
consequences had Rick attempted to cook with this stove inside his tent.
Especially if it was a highly flammable sil-nylon or eVent fabric tent. In
the alternative, perhaps the smarter approach would be to cook in a well
ventilated vestibule with a generous amount of clearance to the fabric
walls.
2) The OP, Jero...@gmail.com, asked about whether he would be better
advised to take a Coleman Fyrestorm or a Optimus Nova to Japan. Until there
are more reviews by users of the Fyrestorm, I would hesitate to take that
stove or the Nova; instead, I think the most reasonable and conservative
choice remains the Primus OmniFuel, simply because it has a proven track
record working well with both liquid fuel and butane/propane canisters.
http://www.backpacker.com/article/1,2646,3805,00.html
3) Here's is some information which may be helpful to backpackers who use
their stoves in cold weather and high altitudes:
Source: The Primus Manual for Himalaya MultiFuel (MFS) and Himalaya VariFuel
(LFS).
By The Primus Team with Till Gottbrath
Cooking in cold weather
1. Using gas in cold weather
Gas does not evaporate, if it is very cold (at sea level: propane at -42°C,
isobutane at -12°C, butane 0°C). You may believe that 100% propane is the
best gas for cold temperatures. Unfortunately 100% propane gas cartridge
contents are prohibited due to the high pressure of propane. The gas must
be mixed with butane and iso-butane. Propane does not mix properly with
butane, though. If you light the stove when it is cold, only the propane
will
flow out, the butane will remain at the bottom of the cartridge. As the
contents
of the cartridge decrease, it will be gradually more difficult to light the
stove, due to the higher portion of butane in the mix. We have optimized the
mixing ratio of these three gases for Primus gas cartridges.
What can you do to make gas evaporate
even in a cold climate?
From -15°C and colder you must warm the cartridge by:
. Putting it under your jacket for 10 minutes before cooking.
. Warming it in some warm water that you have left in your thermos bottle.
. Put it inside your sleeping bag at night (brrrr!).
. Pee on it, (well, we admit that's kind of a strange tip, but in rough
times...).
. Use a Primus Heat Pad. This is a 90 gr. pad that is activated with a
'click'.
Put it under the cartridge. There, it will develop a temperature of about
50°C for 15 minutes. To charge it again, let it boil for 5 min. You can put
it
in your soup, the plastic cover is food proof.
. Turn down the control valve as low as possible. Now hold the gas cartridge
and turn it upside down slowly and very carefully. While doing so,
you must never lift the cartridge higher than the stove itself to avoid a
sudden
burst of flames.
2. Using liquid fuel in cold weather
. Below -20°C, wax and other substances, that are contained in most of
the liquid fuels, will turn thick or solid. Also the leather of the pump
will get stiff. Stuff the fuel bottle under your jacket or in your (partner's)
sleeping bag before you light the stove.
. Be careful that your skin does not contact the fuel. Danger of frost bite
by
fuel evaporating on your skin!
. If the burner (stove) is not hot enough, the fuel will not burn with the
small,
blue flame that it should do, but with a yellow flame - like a fire and also
with
the occasional high flames you have in a fire. Reason: the fuel has not yet
vaporized, but comes to the burner in liquid phase. It actually burns like
an
open fire. The intuitive thing to do is to close the control valve . With
white
gas/petrol that is ok. Then simply wait until the flames become sufficiently
small and then open the control valve more. However, if you do it in the
same
manner with kerosene/paraffin or diesel you will most likely have a problem
because these fuels will create soot that will clog the jet nipple and often
the generator which in turn means that you must clean these. My hint
here for kerosene/paraffin or diesel is: do not close the control valve
fully
but leave it open just a little bit. Close it only so much that you do not
nourish
the big, yellow flames but still some fuel flows through- and by doing
this no soot sediments will develop in the generator, nor in the jet nipple.
Cooking at high altitudes
1. Gas
Most expedition mountaineers use gas at very high altitudes. Why?
1. It's the safest fuel.
2. Gas has the highest energy content.
3. It needs no priming.
4. It leaves almost no residue or toxic substances.
2. Liquid fuel
Liquid fuel is not as good for very high altitudes as gas cartridges,
although
it works well enough in base camps. Since stoves are used a lot there,
one might choose to use kerosene/paraffin. White gas/petrol has a higher
energy content, but for safety reasons I would prefer kerosene/paraffin.
Source: http://tinyurl.com/m5c9h
4) As interesting note, Chris Townsend wrote about an Allanter Leisure
Products ("ALP") stove, which long before the advent of Coleman's PowerMax
cartridges, used a liquid butane/propane feed:
Feb 12 2006 12:26 pm New Coleman Backpacking Stove--Fyrestorm -
rec.backcountry
Many over the years going back to a UK stove in the late 1970s that was
designed for this. It was called the Alp 8100 and had a stand that held
the canister at an angle for liquid feed. I remember it worked quite
well but was a hassle to put together. I've also used various Primus,
MSR and Coleman low profile stoves like this.
Source: http://tinyurl.com/mgjpf
5) With respect to the discussion of Canadian unleaded gasoline with
manganese-based additives, here is some information from Coleman which may
be applicable to other brands, as well:
Q. Can I use unleaded gasoline when Coleman® Fuel is recommended?
A. Unleaded gas should only be used in Coleman® appliances marked as "Dual
FuelT" or Unleaded Fuel" and only the lowest octane unleaded gas available
should be used. Unleaded gas contains additives that are more difficult to
vaporize than the gas itself and the higher the octane rating of the fuel,
the more additives mixed with the gas.
Unleaded gas from Canada should never be used in any Coleman® appliances,
even the "Dual FuelT" and "Unleaded" products, as there is an additive in
the fuel that will damage the tank, valve, generator and burner assembly.
Coleman® "Dual FuelT" and Unleaded" appliances have been designed to handle
the additives in unleaded gas. The use of unleaded gas in any Coleman®
appliance designed for use only with Coleman® Fuel can result in a rapid
build-up of carbon in the generator and damage to the rust-resistant coating
inside the fuel tank.
The cost savings in using unleaded fuel in a Coleman® Fuel appliance would
be rapidly offset by the cost of replacing the generator and eventually the
fuel tank or entire appliance.
Source: http://www.coleman.com/coleman/faq/faqreturn.asp?question=35
6) I have the impression that with the Fyrestorm that once you get past the
first minute or so of pumping and lighting it that its performance on white
gas is adequate. At least, this is according to Rick Dreher's initial
report on the Fyrestorm at BackpackGeartest.org, who wrote, "Once warmed up
and vaporizing well, the white-gas mode Fyrestorm is a steady performer,
happily chugging along in a manner familiar to white gas stove users."
http://tinyurl.com/om7qv Yet, Clyde says that the Fyrestorm's demands on
the user with respect to pumping and tweaking make it suitable to burn white
gas only in an emergency. I am wondering if Clyde might provide any detail
as to whether his experience with the Fyrestorm was any different than that
of Rick Dreher's.
Clyde
> Does having a blend change the boiling temperature or does the
> propane come off first at lower temps? From my experience with starting
> a iso/butane stove for short periods and many times in the cold, the
> propane seems to disappear.
On normal LP stoves, propane does boil off first when below the
vaporization temp of the butane. Not on liquid feed though.
More often, the deteriorating performance while running an LP stove is
due to the cooling effect of expanding gas. For some reason, this rarely
registers with most people even though it's easily solved by a variety
of methods.
Clyde
> But you have to admit that saying that "cold isn't a
> factor even at low altitude" because smart people never let the fuel
> get very cold is kind of an odd argument.
Wouldn't say that about any LP stove that isn't designed to use
liquid-feed (till next year, maybe), even with a tent.
Clyde
> ------------------------
> The manganese will over a period of time gum-up the stove. Coleman has
> said nothing about its detriment to humans in its manual that I am aware
> of? Burning butane will not be effective in extremely cold, low altitude
> environments. Liquid fuel may have to be used sometime. It's informative
> for the public to know that the Fyrestorm has problems with this unleaded
> fuel. The Optimus Nova does not seem to have any undue problems with this
> fuel nor does MSR stoves.
> -------------------------
Since LP and Coleman gas is readily available in Canada, it's rather
moot. Our EPA is the one saying MMT is unhealthy.
> ---------------------------
> Did I mention the new Nova Plus. No. I said "The Optimus Nova has a stable
> track record compared to the 'new' Fyrestrom stove." You are interjecting
> extraneous irrelevant information that avoids or convolutes any real
> reply.
> ---------------------------
Answered you in the first sentence. Claiming a stove that's been on the
market has a better track record than one that is new is blindingly
obvious.
> ----------------------------
> Gateway towns may have these LP canisters but many towns in the interior
> of those countries do not have these canisters but do have petrol and
> kerosene. The Fyrestorm, also, does not burn Kerosene which is used in
> some of the countries (eg. Japan) that you have listed. The Optimus Nova
> (both old & new models) does burn Kerosene, however. The Fyrestorm, more
> correctly, should not be called a mult-fuel stove but rather a Tri-fuel
> stove---LP gas, unleaded auto gasoline, White gasoline (Coleman type
> fuel).
> ----------------------------
For 90% of stove buyers in North America, the Fyrestorm will meet their
needs and finding fuel won't be a problem. If you're going someplace so
remote LP isn't an option, the trip already cost so much that the price
of a stove is nothing. The way airlines are cracking down, you're likely
to have to purchase an empty fuel bottle and liquid fuel (possibly a new
stove if they smell fumes) when you arrive and that may be no less easy
than finding LP.
So far, not one of the burn-anything stoves is a good choice for less
than really remote use. Plate burners are noisy, white gas is a hassle,
kerosene and car gas are always a last resort. I've owned or tested most
of them and keep a couple around for special trips or comparison
purposes. They work but they aren't a pleasure to use.
> ----------------------------
> Interesting comment Clyde. I did not realize, as you suggested, that the
> Backpacker Editor's Choice Award may be based on stove companies
> advertisements in its magazine?
> ---------------------------
Suffice to say, magazine awards are for marketing not helping consumers.
Don't trust any of them, ever.
> ---------------------------
> Why do you say that Clyde? What criteria do you use in selecting a product
> that you intend to purchase? Do you buy a product simply because of :Brand
> Name, functionality innovation, or price? Some people that I know simply
> make a decision based on price---If it cost more it must be better.
>
> If you consider price and safety of all trekking stoves and their
> advertised company statistics, some independent/impartial review becomes
> necessary for most people who are considering the purchase of these
> stoves. Therefore I do not consider it "Hogwash" nor a "total waste of
> time and money."
Stoves aren't handmade items and nobody is cherry picking review
samples. Even on clothing or sleeping bags, production tolerances are so
tight these days that variation is all but non-existant. Purchasing a
single sample in a store is no better than getting one shipped from the
warehouse. For the exercise to have more meaning than a marketing
gimmick would require far more time and resources than any magazine has
available.
It's still up to the consumer to test their own sample before commiting
to a major trip. Anyone who soley trusts a review (don't care who wrote
it), manufacturer's reputation, or price deserves what they get when
something goes wrong.
I don't know about washing machines or floor wax but, for every category
that Consumer Reports touches on gear that I do know about, they are a
shining example of how to fuck up a review -- buying in stores doesn't
overcome incompetance.
Clyde
> 1) I thought the smart people knew enough NOT to cook inside a tent
> because of the danger of carbon monoxide poisoning. And not to mention
> the danger of a liquid fuel stove flare-up or the danger of fuel spilling
> on the floor during priming.
Utter nonsense, it's SOP. Kill all the lawyers, then open a vent. If
you're forced to use liquid fuel stoves instead of LP, light them
outside of the vestibule before retreating.
> 2) The OP, Jero...@gmail.com, asked about whether he would be better
> advised to take a Coleman Fyrestorm or a Optimus Nova to Japan. Until there
> are more reviews by users of the Fyrestorm, I would hesitate to take that
> stove or the Nova; instead, I think the most reasonable and conservative
> choice remains the Primus OmniFuel, simply because it has a proven track
> record working well with both liquid fuel and butane/propane canisters.
Lame as an LP stove, more like an aftethought. Okay otherwise if you
don't mind the weight.
> 6) I have the impression that with the Fyrestorm that once you get past
> the first minute or so of pumping and lighting it that its performance on
> white gas is adequate. At least, this is according to Rick Dreher's
> initial report on the Fyrestorm at BackpackGeartest.org, who wrote, "Once
> warmed up and vaporizing well, the white-gas mode Fyrestorm is a steady
> performer, happily chugging along in a manner familiar to white gas stove
> users." http://tinyurl.com/om7qv Yet, Clyde says that the Fyrestorm's
> demands on the user with respect to pumping and tweaking make it suitable
> to burn white gas only in an emergency. I am wondering if Clyde might
> provide any detail as to whether his experience with the Fyrestorm was any
> different than that of Rick Dreher's.
Any stove that requires 80 pumps with a full tank is a joke. Start up is
less safe IMHO than normal priming. Plus it's a nuisance to get in and
out of the bottle for refilling and the hose dribbles fuel when removed.
Stick with LP and be happy.
J. Curl
J. Curl
>
> On normal LP stoves, propane does boil off first when below the
> vaporization temp of the butane.
Not true. Propane "boils off first" at any temperature. That is to say,
the percentage of propane in the vapor is higher than the percentage of
propane in the liquid whether at room temperature or at sub-freezing.
The propane percentage in the liquid diminishes a little faster at
colder temperatures, but the difference compared to warmer temperatures
is relatively minor.
> More often, the deteriorating performance while running an LP stove is
> due to the cooling effect of expanding gas.
Actually the main reason for cooling is due to the energy required to
vaporize the liquid fuel. Cooling due to gas expansion is a secondary
effect.
> For some reason, this rarely
> registers with most people even though it's easily solved by a variety
> of methods.
The reason is simple. People are, on average, not particularly
intelligent. I'm sure you have noticed this.
Eugene Miya
>> igloo, nod to Ed).
>
>True enough. But you have to admit that saying that "cold isn't a
>factor even at low altitude" because smart people never let the fuel
>get very cold is kind of an odd argument.
This is / was Marcus' argument.
That's Marcus for you.
Amazing, 2 people I've met.
--
Eugene Miya
David <n...@mindspring.com> wrote:
>Clyde y...@figureitout.com:
>anytime it's below 0°F, smart people are cooking inside a tent
>
>of the danger of carbon monoxide poisoning. And not to mention the danger
>of a liquid fuel stove flare-up or the danger of fuel spilling on the floor
>during priming.
Wind, driving snow, extreme cold, etc. have for decades, almost a
century of people cooking inside a tent. True, some inexperienced novices
from Comm. Richard Byrd on to a recent Annapurna trip, didn't have
adequate ventilation, but to varyinig degrees of winding and driven
snow, you would have an amusing time cooking outside a tent.
Clyde I can trust.
--
Clyde
> The propane percentage in the liquid diminishes a little faster at
> colder temperatures, but the difference compared to warmer temperatures
> is relatively minor.
But when you're starting at 20% which accounts for a lot of extra BTUs,
doesn't that difference become more significant by the time the bottle
is 2/3 spent? I'm just a cook.
J. Curl
No. The energy content of propane (by weight) is nearly identical to
that of butane or isobutane. What you lose with the change in fuel
composition is pressure. You don't notice this at room temperature
because the pressure, although diminished, is high enough to drive the
stove at full throttle. But at colder temperatures you may already be
close to the threshold pressure and a further loss results in a stove
that runs weakly or even sputters out.
Of course such details are not required by an experienced cook. You
already *know* how your stove works in the field.
David
I think the most reasonable and conservative choice remains the Primus
OmniFuel, simply because it has a proven track record working well with both
liquid fuel and butane/propane canisters.
Clyde y...@figureitout.com
Lame as an LP stove, more like an aftethought. Okay otherwise if you don't
mind the weight.
David n...@NOSPAMnymindspring.com
Lame??? The Primus OmniFuel? Clyde, ya gotta be kidding me. On LP
butane/propane, this baby burns H- O-T. I've got the partially melted MSR
XPD aluminum heat exchanger to prove it. But hey, just don't take my word
for it.
In a comparison of boiling times of 25 stoves on pages 282 and 283 in Chris
Townsend's "The Backpacker's Handbook" (McGraw-Hill, 3rd edition, 2005)
http://www.auchnarrow.demon.co.uk, the Primus OmniFuel was fastest, with the
exception of the Coleman Xtreme (30 seconds faster) and the Coleman
Outlander F1 Ultralight and the F1 PowerBoost (tie). And other publications
similarly have confirmed the Primus OmniFuel's performance.
http://www.outdoor-magazin.com/multifuelkocher_primusomnifuel.111732.htm
Clyde
> But at colder temperatures you may already be
> close to the threshold pressure and a further loss results in a stove
> that runs weakly or even sputters out.
So what happens when you add an internal pressure regulator to the
stove? wink, wink, nod, nod
Clyde
> Lame??? The Primus OmniFuel?
Yes, with LP. Just because you can, doesn't mean you should. Way better
with other fuels though, for a heavy noisy stove.
MB
>>> Anytime it's below 0=B0F, smart people are cooking inside a tent (or
>>> igloo, nod to Ed).
J Curl >
>> True enough. But you have to admit that saying that "cold isn't a
>> factor even at low altitude" because smart people never let the fuel
>> get very cold is kind of an odd argument.
Eugene >
> That's Marcus for you.
Ok, I'll bite (with a 'k', not 'c', btw).
Sure. Smart people may cook inside a tent. For the
convenience of the operator, to protect the stove
from wind, spin-drift and whatever. But - I'm sure -
*not* to warm up the fuel!
Assume, for the sake of the argument, that the
cartidge (stove) is operable above -20C, and the
ambient is -40C. For how long do you have to sit
with the cartidge in your tent before it has warmed
up 20C? Chanses are that you won't be cooking anytime
soon, and that you'll end up hiking with the cartidge
in your pants, applying heat pads and whatever - ie,
doing exactly the things that you have to do with gear
that won't work in the cold.
You may need to use the stove enroute, to melt snow
for drinking. In low/no wind conditions, there's no
point in pitching a shelter for short(ish) pauses.
Never mind building an igloo. The cold cartidge will
end up in the pants - no fun.
Petrol stoves have problems in cold conditions too, but
they *are actually used* in the cold at low altitude. I'd
be interested in hearing whether someone has actually used
one of these liquid-fed LP-stoves at, say, -40C at sea level.
Nevertheless, assuming skill, availability and acceptability,
wood fire is imo by far the most reliable source of heat in
cold conditions.
Chris Townsend
<y...@figureitout.com> writes
>David <n...@mindspring.com> wrote:
>
>> I would think that most other butane stoves which preheat (vaporize) their
>> fuel could equal the Fyrestorm, if the user carefully inverted the fuel
>> cartridge to avoid the problem of diminished vapor pressure in the canister
>> due to the cold.
>
>Of course none of those are designed to hold an inverted cartridge so
>you have to jury rig them. The screw-on adaptor for Powermax stoves puts
>them in contention but is bulkier and heavier (they're decent stoves
>alone if you can find the PM fuel).
This last winter/spring I've been using a Primus Gravity stove with a
variety of cartridges (Primus. Coleman, GoGas). Inverting the canister
makes a huge difference in below freezing temperatures and with almost
empty cartridges. I haven't bothered with any complex jury rig. Just
propping the cartridge against a stone, tent peg, boot or anything
works.
Chris Townsend
<y...@figureitout.com> writes
>MB <*@*.*> wrote:
>
>> In contrast, assuming that LP-canisters could be readily found seems
>> simply absurd.
>
>referring to the European attractions of Siberia or the Kamchatka
>peninsula.
Which canisters though? Last year on Corsica I could only find Campingaz
CV resealable cartridges on the GR20, which is a very popular long
distance walk. I has an MSR Superfly stove so this wasn't a problem (I'd
been told I'd be unlikely to find anything else).
David
> This last winter/spring I've been using a Primus Gravity stove
David n...@DELETEmindspring.com:
Chris, were you using the Primus Gravity MF?
http://www.primus.se/primus/Products/product.asp?ItemId=21359
Primus describes it as a "combination of Gravity EF and Gravity VF." This
stove burns butane/propane canisters, plus white gas (Coleman fuel),
unleaded gasoline and kerosene. This 10,5000 BTU stove weighs only 8.4
ounces - 239 grams, without the liquid fuel pump. It might be a better
choice than the Coleman Fyrestorm. And it might be an alternative to the
Primus OmniFuel or the Karrimor Fleixifuel. But Germany's Outdoor Magazin
in September, 2005, said the Gavity EF was only a good choice for the
"Leichtfreaks" and awarded it only 2 out 5 stars. What do you think, Chris?
From http://www.outdoor-magazin.com/sixcms/detail.php?id=96028 - here's a
machine translation from German by Google - anyone care to correct any
glaring errors?
Primus Gravity MF Light equipment presses the backpack weight and increases
the route fun. Also Primus knows and presents as easy alternative to the
outdoor test winner Omnifuel the Gravity MF (100 euro). It weighs 490 gram
with tool, wind protection, bottle and bag - 90 g less than the counterpart
of MSR, the Whisperlite international. Advantage of these digesters: If' s
gives on the way neither pure gasoline nor Tankstellensprit, one can feed
her also with petroleum. On route the Gravity MF pleases by the low, safe
conditions and the handy pot edition. Also the Flammenregulierung functioned
well and the Kochzeit of 4:50 min for the litre of eight degrees cold water
is quite short. But: Preheating requires much feeling and experience - one
recognizes often too late, how much gasoline withdrew for preheating.
Consequence: blazing flames. Much fine feeling (and fat) requires also the
pump clutch, whose sealing ring wears otherwise rapidly. In addition the
tool seizes to nozzle changes and - hardly clean. Primus wants to repair the
last two points until next year.
Result: A good digester - however only for Leichtfreaks, which are occupied
gladly intensively with their equipment. Primus Gravity MF
John Decker
says...
David...this may be of some interest to you about the Primus Gravity MF.
JD
David
stove who complained about fuel nozzle clogging while using paint thinner
for cooking. Primus warns users not to use alcohol in their MultiFuel stove
manual http://tinyurl.com/m5c9h because the internal seals are not
chemically compatible with it, so God knows what paint thinner will do.
BTW, here's the English language page for the Primus Gravity MF.
http://www.outdoorsmagic.com/news/article/mps/UAN/3335/v/1/sp
Outdoors Magic, on June 5, 2005, reviewed the Primus Gravity stove with the
built-in piezo electric ignition which uses LP canisters and is sometimes
known as the Gravity PF. The article said, "So far it's the best remote
burner gas stove we've ever used."
http://www.primus.se/primus/Products/product_sheet.asp?ItemId=21359
MB
of the Coleman Fyrestorm, from my point of view:
1. Fyrestorm (or any liquid-fed LP stove) is *not* intrinsically
winter capable like common petrol and alcohol stoves. F should
however do much better than typical LP stoves.
2. There is no information on the actual cold-weather performance
of Fyrestorm. (Coleman didn't bother to reply my e-mail, btw.)
The best info is the estimate courtesy of J Curl; -10F at sea
level (with 1:4 propane/isobutane).
3. Cooking inside a tent is irrelevant - of course - given the
context.
Chris Townsend
writes
>Concluding (trolling Clyde?) the discussion of the winter-capability
>of the Coleman Fyrestorm, from my point of view:
>
>1. Fyrestorm (or any liquid-fed LP stove) is *not* intrinsically
>winter capable like common petrol and alcohol stoves. F should
>however do much better than typical LP stoves.
The Coleman X stoves with Powermax cartridges work fine down to -15C at
sea level (and maybe below, I can't say). The problem is cartridge
availability. They're just about impossible to get in Britain.
The Fyrestorm appears to work in cold weather due to the inversion of
the cartridge, making it a liquid feed. This shouldn't be any different,
as far as I can see, from inverting the cartridge with other stoves with
preheat tubes. This does work to some extent but not as well as Powermax
cartridges, which have a 60/40 butane/propane mix.
David
someone who has used the Primus Gravity MF stove http://tinyurl.com/mntwn.
Perhaps Chris Townsend might share his experience in this regard, if he has
used the "MF" version.
The reason is that the Gravity MF is an intriguing competitor to Coleman's
Exponent Fyrestorm. To begin with, its weight is very close to that of the
titanium version of the Fyrestorm, to wit, 215 grams (7.6 ounces) for the
Fyrestorm versus 239 grams (8.4 ounces) for the Gravity MF, based on the
weights of the burners by themselves.
Yet the street price of the Gravity MF is as low as $76.25
http://tinyurl.com/qsuxd, which is not only dramatically less than the list
price of the titanium Fyrestorm ($189), but also the stainless steel
Fyrestorm ($149).
Moreover, although both the Gravity and the Fyrestorm stoves can burn LP Gas
(and Chris has noted in this thread that the Gravity works with an LP
canister inverted for the liquid feed of a butane/propane mix), and both can
also burn white gas (Coleman fuel) and unleaded automotive gasoline, only
the Gravity MF (and the Gravity VF) can also burn kerosene.
However, according to the Outdoor-Magazin article I posted in this thread on
6/16/2006 @ 2:50 p.m., the Gravity MF as a liquid fuel stove is less than
perfect. And the same can be said of the Fyrestorm, judging from what has
been reported in this thread. Therefore, although we have a choice of
three manufactures of stoves which can burn both butane/propane LP gas and
liquid fuels, offering us a total of six stoves which have significant
differences in price, weight, design and materials, namely 1) the Karrimor
Flexifuel, 2) the Primus MultiFuel, 2) the Primus OmniFuel, 3) the Primus
OmniFuel Titanium, 4) the Primus Gravity MF, 5) the Coleman Exponent
titanium Fyrestorm and the 6) stainless steel Coleman Exponent Fyrestorm, I
would conclude that for most of us the Primus OmniFuel offers a good
combination of user friendly performance and a not too extravagant price. I
would also say to the orignal poster ("OP") that the OmniFuel is a better
choice than the Optimus Nova, simply because the Nova can only burn liquid
fuels.
Chris Townsend
<n...@mindspring.com> writes
David, I've used the Gravity EF and the Gravity VF but not the new
Gravity MF and reviewed them for the UK magazine TGO. I think the EF,
the one that runs just on cartridges, is superb. It's very powerful and
simmers well. The test model weighs 261 grams. This is the stove I've
been using with inverted cartridges.
I'm not so keen on the Gravity VF as I found priming it messy and with a
great deal of flaring. Once lit it burns fine.
I've not found the Flexifuel. Primus MultiFuel or Omnifuel very
efficient with liquid fuel. They all work better with cartridges. The
Nova and the various MSR liquid fuel stoves are better. The Nova is my
favourite because of the fast priming and the lack of drips when
releasing the pressure from the fuel bottle and detaching it from the
stove. If I was going for just one stove for cartridges and liquid fuel
it would be the Omnifuel.
>
David
Bill Tuthill
>
> David, I've used the Gravity EF and the Gravity VF but not the new
> Gravity MF and reviewed them for the UK magazine TGO. I think the EF,
> the one that runs just on cartridges, is superb. It's very powerful and
> simmers well. The test model weighs 261 grams. This is the stove I've
> been using with inverted cartridges.
Picture of this stove, which sells for under $70.
http://www.libertymtn.com/catalog.php?type=product&id=94149
Previously you said this about inverting the cartridges.
My question is, doesn't the valve get dirty sitting on the ground?
Chris Townsend
>Chris Townsend <Ch...@delete.auchnarrow.demon.co.uk> wrote:
>>
>> David, I've used the Gravity EF and the Gravity VF but not the new
>> Gravity MF and reviewed them for the UK magazine TGO. I think the EF,
>> the one that runs just on cartridges, is superb. It's very powerful and
>> simmers well. The test model weighs 261 grams. This is the stove I've
>> been using with inverted cartridges.
>
>Picture of this stove, which sells for under $70.
>http://www.libertymtn.com/catalog.php?type=product&id=94149
>
>Previously you said this about inverting the cartridges.
>My question is, doesn't the valve get dirty sitting on the ground?
I guess it could if it was pushed into mud or soft ground but I haven't
had a problem with this. The valve is screwed tight into the cartridge
and so is pretty well protected.
MB
> The Fyrestorm appears to work in cold weather due to the inversion of
> the cartridge, making it a liquid feed. This shouldn't be any
> different, as far as I can see, from inverting the cartridge with
> other stoves with preheat tubes. This does work to some extent but not
> as well as Powermax cartridges, which have a 60/40 butane/propane mix.
As J.Curl already pointed out, fuel vapour pressure is still needed
to operate the stove in order to overcome the atmospheric pressure
and friction of the fuel-flow. And, also, that the hydrostatic pressure
of the fuel (gravity feed) is of little significance here.
At -40C, the fuel-vapour pressures are
Propane 857 mmHg
Butane 139
Isobutane 215
No way that a 60/40 butane/propane mix could work.
Not without getting replacement air, anyway. But would gravity
feed suffice even with replacement air available? Anyway,
puncturing the cartidge bottom to let air in doesn't seem like
a good idea anyway ;)
Chris Townsend
writes
Well, I haven't used one, or any stove, at -40C. But at -20 the Powermax
cartridges and X stoves do work.
J. Curl
I tossed a few standard canisters into the freezer several years ago
and measured their pressures. At sea level, and about -20°C, they
all had enough pressure to drive a regular vapor feed stove.
18 psig -- MSR Isopro
20 psig -- Markill
12 psig -- Snowpeak
I don't know what's in these canisters -- both MSR and Snowpeak
claim to have the same 20/80 mixture but they have different initial
pressures and the pressures over the lifetimes of the two are quite
different. Likewise, the Jetboil canisters (also supposedly 20/80
propane/isobutane) follow yet another curve.
They all most certainly contain some higher volatility components
which give them initial pressures higher than a pure 20/80 mixture
would indicate. In vapor feed stoves the pressure drops very quickly
at first as these components are largely lost; after this, the pressure
falls in a nearly linear fashion as the propane concentration declines.
But in a liquid feed stove you'd have the benefit of this higher
"initial" pressure presumably throughout the life of the canister.
How low in temperature would it work? Not sure, but I suspect that
for most *practical* purposes, low enough.
Chris Townsend
Curl <jhc...@yahoo.com> writes
In actual use I haven't found meaningful differences between these and
other cartridges I've used - Coleman, Primus, GoGas.
>
>They all most certainly contain some higher volatility components
>which give them initial pressures higher than a pure 20/80 mixture
>would indicate. In vapor feed stoves the pressure drops very quickly
>at first as these components are largely lost; after this, the pressure
>falls in a nearly linear fashion as the propane concentration declines.
>
>But in a liquid feed stove you'd have the benefit of this higher
>"initial" pressure presumably throughout the life of the canister.
I haven't found it quite as good as this! The initial pressure drops
quickly but acceptable pressure lasts for around 4/5 of the contents and
then fades away at below freezing temperatures so that cartridges have
to be warmed or shaken to produce enough heat.
>
>How low in temperature would it work? Not sure, but I suspect that
>for most *practical* purposes, low enough.
>
I'm certainly happy using inverted cartridges down to -12C.
J. Curl
>
> >But in a liquid feed stove you'd have the benefit of this higher
> >"initial" pressure presumably throughout the life of the canister.
>
> I haven't found it quite as good as this! The initial pressure drops
That's interesting. How did you measure the pressure and temperature?
> ...but acceptable pressure lasts for around 4/5 of the contents and
> then fades away at below freezing temperatures so that cartridges have
> to be warmed or shaken to produce enough heat.
Does shaking (with a cold gloved hand) really help? I don't understand
why it would.
Chris Townsend
Curl <jhc...@yahoo.com> writes
>Chris Townsend wrote:
>>
>> >But in a liquid feed stove you'd have the benefit of this higher
>> >"initial" pressure presumably throughout the life of the canister.
>>
>> I haven't found it quite as good as this! The initial pressure drops
>> quickly...
>
>That's interesting. How did you measure the pressure and temperature?
I didn't measure it scientifically. But what I've found is that with a
new cartridge the pressure is so high that it can blow the flame out.
This calms down in a few minutes. The pressure is still very high for
another ten minutes or so then eases off. I've found this with a number
of cartridge and stove combinations and now routinely keep the stove
turned down until the cartridge is about 2/3 full.
>
>> ...but acceptable pressure lasts for around 4/5 of the contents and
>> then fades away at below freezing temperatures so that cartridges have
>> to be warmed or shaken to produce enough heat.
>
>Does shaking (with a cold gloved hand) really help? I don't understand
>why it would.
Shaking really does help. I do it often. So does putting your hands
round the cartridge to warm it but this is slower and colder than
shaking. Neither increases the heat output for more than a few minutes
however so they need to be done repeatedly.
J. Curl
> In message <1150998191.4...@m73g2000cwd.googlegroups.com>, J.
> Curl <jhc...@yahoo.com> writes
> >Chris Townsend wrote:
> >>
> >> >But in a liquid feed stove you'd have the benefit of this higher
> >> >"initial" pressure presumably throughout the life of the canister.
> >>
> >> I haven't found it quite as good as this! The initial pressure drops
> >> quickly...
> >
> >That's interesting. How did you measure the pressure and temperature?
>
> I didn't measure it scientifically. But what I've found is that with a
> new cartridge the pressure is so high that it can blow the flame out.
> This calms down in a few minutes. The pressure is still very high for
> another ten minutes or so then eases off. I've found this with a number
> of cartridge and stove combinations and now routinely keep the stove
> turned down until the cartridge is about 2/3 full.
I have done tests with these cartridges, but they're more of the lab
variety (actually my kitchen) than field tests. So while the data are
more accurate, there could be important differences as well.
http://img476.imageshack.us/img476/7652/liquidfeed2ow.jpg
The plots in the image linked above are of two Snowpeak 220g canisters.
Each was weighed, equilibrated in a water bath at 60°F, and then the
pressure was measured. For the lower curve, vapor was vented (and
burned at a remote stove) for a period of time, then the canister was
again weighed and the pressure measured. This was repeated until the
canister was empty.
I also did a quick test of inverted (liquid) feed. A second canister
was measured as above, but then the canister was turned upside down
prior to opening the valve and approximately half the liquid fuel was
forced out.
Only two data points for the inverted case, but while the pressure does
drop, it is pretty clear that the initial loss of pressure suffered
when releasing the vapor does not happen. The pressure at 45% full
is still as high as the vapor feed is at 98% full.
So one is left to puzzle why it does happen when you use your stove
in liquid feed mode in the field. Could it be that the fuel is
vaporizing in your stove's valve, essentially negating the value of
liquid feed?
> >> ...but acceptable pressure lasts for around 4/5 of the contents and
> >> then fades away at below freezing temperatures so that cartridges have
> >> to be warmed or shaken to produce enough heat.
> >
> >Does shaking (with a cold gloved hand) really help? I don't understand
> >why it would.
>
> Shaking really does help. I do it often. So does putting your hands
> round the cartridge to warm it but this is slower and colder than
> shaking. Neither increases the heat output for more than a few minutes
> however so they need to be done repeatedly.
I have tried this a couple times with a regular stove (not liquid feed)
after someone had told me it would help. It never did anything that I
could detect other than interrupt the cooking. Interesting that it
makes a difference with an inverted canister. You can't be generating
heat that way, so maybe you're somehow helping the fuel to move through
the line?? Weird.
Chris Townsend
I guess that's possible. The value of liquid feed isn't negated until
the cartridge is almost empty though. Heat output is adequate in liquid
feed mode but not in vapour feed mode. Also, I find that in above
freezing temperatures when the cartridge is almost empty inverting it
increases the heat output so I now do this too rather than wait for the
last fuel to very slowly burn off in vapour feed mode.
>
>
>> >> ...but acceptable pressure lasts for around 4/5 of the contents and
>> >> then fades away at below freezing temperatures so that cartridges have
>> >> to be warmed or shaken to produce enough heat.
>> >
>> >Does shaking (with a cold gloved hand) really help? I don't understand
>> >why it would.
>>
>> Shaking really does help. I do it often. So does putting your hands
>> round the cartridge to warm it but this is slower and colder than
>> shaking. Neither increases the heat output for more than a few minutes
>> however so they need to be done repeatedly.
>
>I have tried this a couple times with a regular stove (not liquid feed)
>after someone had told me it would help. It never did anything that I
>could detect other than interrupt the cooking. Interesting that it
>makes a difference with an inverted canister. You can't be generating
>heat that way, so maybe you're somehow helping the fuel to move through
>the line?? Weird.
I use it in vapor feed mode too. I only use it with hose-connected
stoves so it doesn't interfere with cooking (in fact I only do it when
reduced heat output is interfering with cooking) and I can shake the
cartridge vigorously.
>
Ed Huesers
>> So one is left to puzzle why it does happen when you use your stove
>> in liquid feed mode in the field. Could it be that the fuel is
>> vaporizing in your stove's valve, essentially negating the value of
>> liquid feed?
Chris Townsend wrote:
> I guess that's possible. The value of liquid feed isn't negated until
> the cartridge is almost empty though. Heat output is adequate in liquid
> feed mode but not in vapour feed mode. Also, I find that in above
> freezing temperatures when the cartridge is almost empty inverting it
> increases the heat output so I now do this too rather than wait for the
> last fuel to very slowly burn off in vapour feed mode.
Would looking at the system as a geyser explain any of the oddities
or is there a check valve in the system somewhere?
Geysers are pretty temperamental.
Ed Huesers
Http://www.grandshelters.com
MB
> Well, I haven't used one, or any stove, at -40C. But at -20 the
> Powermax cartridges and X stoves do work.
If this powermax is 40/60 (by mass) propane/butane,
the fuel vapour pressures are roughly (*):
810 mmHg at -20C; 40/60
340 mmHg at -40C; 40/60 propane/butane
If it's isobutane, rather than butane, then
950 mmHg at -20C; 40/60 propane/isobutane
410 mmHg at -40C; 40/60 propane/isobutane
Compare the above to the normal (sea level) atmospheric
pressure, 760 mmHg.
Based on the above, a 40/60 propane/butane stove could
work at -20C, but not at -40C. The break even point would
be at about -25C with isobutane, but this neglects the
surplus pressure required to overcome the flow friction.
(* Antoine's equation/parameters, calculators at eg
http://www.s-ohe.com and Raoult's law)
Chris Townsend
writes
I won't try using one at -40C then :-).
The Powermax cartridge is 40/60 butane/propane. No isobutane.
The cartridge is made from thin aluminium rather than steel and is much
lighter than standard cartridges. There is a plastic tube with a metal
section at the end inside the cartridge through which the liquid gas is
drawn.
J. Curl
>
> If this powermax is 40/60 (by mass) propane/butane,
> the fuel vapour pressures are roughly (*):
>
> 810 mmHg at -20C; 40/60
> 340 mmHg at -40C; 40/60 propane/butane
>
> If it's isobutane, rather than butane, then
>
> 950 mmHg at -20C; 40/60 propane/isobutane
> 410 mmHg at -40C; 40/60 propane/isobutane
>
> Compare the above to the normal (sea level) atmospheric
> pressure, 760 mmHg.
>
> Based on the above, a 40/60 propane/butane stove could
> work at -20C, but not at -40C. The break even point would
> be at about -25C with isobutane, but this neglects the
> surplus pressure required to overcome the flow friction.
>
> (* Antoine's equation/parameters, calculators at eg
> http://www.s-ohe.com and Raoult's law)
I could not reproduce your calculations.
For 40/60 (by mass) propane/butane, the mole fractions are
0.468 and 0.532 respectively. Saturated vapor pressures
for the pure substances are 1834 and 340.4 mmHg (-20°C),
and 832.6 and 126.7 mmHg (-40°C) (from the NIST website).
Applying Raoult's Law gives total vapor pressures:
1039 mmHg @ -20°C -- 40/60 (w/w) propane/n-butane
457 mmHg @ -40°C -- 40/60 (w/w) propane/n-butane
The break even point at sea level would be at about -28°C
for a mixture with normal butane (-30°C for isobutane).
Surely by *that* point you'd be in your tent!
But if not, answer this: below what temperature will a
petrol stove start to have trouble? Alpinist Andy
Kirkpatrick believes that it is -20°C.
Chris Townsend
Curl <jhc...@yahoo.com> writes
I've several petrol stoves at -25C without trouble - Optimus Nova, MSR
Whisperlite Internationale, MSR X-GK II, MSR Dragonfly. They take longer
to prime but once going work fine.
It is depressing watching a block of ice sitting in a pool of water and
doing nothing in a pan on a roaring stove however!
>
MB
> I could not reproduce your calculations.
No wonder. Embarrassingly enough, my molar fractions were
reversed. Thanks for pointing out my error.
> The break even point at sea level would be at about -28°C
> for a mixture with normal butane (-30°C for isobutane).
In practice, the lowest operation temperature should be
a bit higher, as some excess pressure is required to overcome
the friction at sufficient flow rates.
> Surely by *that* point you'd be in your tent!
Uhm, why? And how would it help anyway?
Assume it's -40C, and your stove would work at -25C. You're
on the move, have run out of water in your thermos, and need
some more. So you stop for a brief cooking break.
Now you pull out your stove from your pack. The cartidge is
at ambient temp, -40C. Not a chance.
So, you pull out your tent too? Why? Besides, pitching a tent
in very cold temps is a handful, and, btw, is not even possible
with many (most?) tents. High wind is a different thing, but for
mere cold there's little point bothering with a tent for a pause.
But assume that you actually do pitch your tent. Then what?
It's just as cold as everything else. You won't be cooking any
time soon, if you plan to warm up your stove by just spending
time with it inside your tent.
It might be ok by the morning, but if you need your stove in
the evening, or enroute, you'll have to use (more direct)
body heat, heat pads etc to warm it up. Ie, the usual things
to do with gear that won't work when cold.
> But if not, answer this: below what temperature will a
> petrol stove start to have trouble? Alpinist Andy
> Kirkpatrick believes that it is -20°C.
Huh?! I thought that Petrol stoves are standard kit on
Polar trips. Anyway, I've used my MSR XGKII below -30C.
The typical problem with such stoves is failing to
pressurize. This is because the pump valve gets 'dry' in
the cold. Adequate lubrication helps to maintain or restore
the valve seal. This is the only problem I've had.
Plastic pump parts may get fragile and fail. I'd prefer a
steel pump (eg Optimus Explorer) rather than MSR's.
Petrol (gasoline) works well in cold temps, but others,
like diesel fuel, lamp petrol (kerosine) are problematic,
and should at least be of Arctic grade.
Simple ethanol stoves (eg Trangia) are reliable. Separate
preheating is required in cold conditions (unlike warmer
weather). Providing sufficient heat output is a problem,
and proper shielding (as in the bigger Trangias) is a must.
J. Curl
> In practice, the lowest operation temperature should be
> a bit higher, as some excess pressure is required to overcome
> the friction at sufficient flow rates.
True. It's also likely that the 40/60 mixture is not pure but
includes other components as well. The pressure may be
higher than we're calculating, just as in other canisters.
> > Surely by *that* point you'd be in your tent!
>
> Uhm, why? And how would it help anyway?
The heat from the stove warms the interior of the tent.
Additionally, the fuel cartridge can be placed in close
proximity to the heat source.
Of course there is a bootstrap problem. You'd need to
use some method to initially warm the canister. Petrol
stoves require preheating as well, but it's more of a
built in function.
> > But if not, answer this: below what temperature will a
> > petrol stove start to have trouble? Alpinist Andy
> > Kirkpatrick believes that it is -20°C.
>
> Huh?! I thought that Petrol stoves are standard kit on
> Polar trips.
Here's the quote from Andy's website (psychovertical.com):
"Good quality liquid burning stoves are not [affected]
by the cold until the temperature drops below -20C - at
which point impurities may develop in the fuel,
clogging the stove. Therefore anyone venturing into
really cold conditions must use a stove that is clog
resistant and easy to clean and maintain. Saying that
you'd be hard pressed to be cooking in that temperature
while in tent, plus once the stove is lit the
temperature will soon rise."
> Anyway, I've used my MSR XGKII below -30C.
No doubt. I wasn't enquiring about a hard threshold
temperature. Rather, below what temperature do such stoves
start to become problematic? My guess -- and it's really
just a guess -- is that most stoves would have problems
at -40°C.
Clyde
>
> Assume it's -40C, and your stove would work at -25C. You're
> on the move, have run out of water in your thermos, and need
> some more. So you stop for a brief cooking break.
>
> Now you pull out your stove from your pack. The cartidge is
> at ambient temp, -40C. Not a chance.
>
> So, you pull out your tent too? Why? Besides, pitching a tent
> in very cold temps is a handful, and, btw, is not even possible
> with many (most?) tents. High wind is a different thing, but for
> mere cold there's little point bothering with a tent for a pause.
Step A) pull Zdarsky tent out of pack and get inside.
(http://www.integraldesigns.com/product_detail.cfm?id=731&CFID=7378347&C
FTOKEN=43005992&mainproducttypeid=1)
Step B) pull warm butane cartridge out of expedition parka internal
pocket, attach to stove, and light.
Alternative B) pop the metal disk on the reusable Primus Heat Pad and
place pad in cavity of inverted cartridge.
Step C) start unzipping clothing as temperature inside rapidly increases
while your water boils.
If you really insist on standing out in the cold (why?), there's this
option:
http://www.mountainhardwear.com/Product.aspx?top=3&prod=649&cat=50&viewA
ll=False
Clyde
> My guess -- and it's really
> just a guess -- is that most stoves would have problems
> at -40蚓.
And even -40蚌 too!
John Decker
Actually Ed...Beer and Beans could be the answer rather that a comparison to
geyser. The generation of self-serving methane flatulence in one of your ice
enclaves could potentially extend precious fuel and save the day. Although a
check valve system may be dependent on attitude and temperment of the cliental.
JD
Ed Huesers
I eagerly await the results of any testing you'd like to do.
Myself... I'll continue to look at the fuel system as a geyser,
blowing gas back up the fuel line and all the way into the tank at times.
I've heard before that there is a check valve in the purchased
canisters so one can't refill them but I've never had confirmation of it.
Ed Huesers
http://www.grandshelters.com
J. Curl
> The generation of self-serving methane flatulence in one of your ice
> enclaves could potentially extend precious fuel and save the day.
There is no methane in the flatus of many, if not most, adults.
There is some hydrogen though.
Ed Huesers wrote:
> Myself... I'll continue to look at the fuel system as a geyser,
> blowing gas back up the fuel line and all the way into the tank at times.
Doesn't the pressure gradient in a geyser go from bottom (high
pressure) to top (low), exactly the opposite of an open inverted
canister of fuel?
> I've heard before that there is a check valve in the purchased
> canisters so one can't refill them but I've never had confirmation of it.
Nah. It's just a spring loaded plunger sort of thing. When you (or
your stove) depresses that little spindle on top of the canister it
opens the valve.
Ed Huesers
>>Myself... I'll continue to look at the fuel system as a geyser,
>>blowing gas back up the fuel line and all the way into the tank at times.
J. Curl wrote:
> Doesn't the pressure gradient in a geyser go from bottom (high
> pressure) to top (low), exactly the opposite of an open inverted
> canister of fuel?
As soon as the liquid fuel touchs something warm enough to vaporise
it, the pressure in that area is greater and it would blow the liquid
back up the line until the gas cooled enough to turn back into a liquid
state. The original gas could have been traveling fast enough that, with
it's own momentum, it over shot the area in the generator where heat and
vaporization would be in equilibrium and it would be an eruption back up
the line or into the tank.
Then, when the gas is pushing the liquid, there is also the momentum
of the gas again, the gas will cool and cause a vacuum sucking the fuel
down the line with even more speed and momentum.
Normally, there are orifices in a fuel system to stop these surges
but when approaching the extreme cold mentioned...
Chris talked of moving the tank and it worked better. There may be
high spots in the line where the gas has warmed the line enough and the
gas doesn't turn to liquid but remains a gas pocket where the liquid
won't flow over with just gravity.
>>I've heard before that there is a check valve in the purchased
>>canisters so one can't refill them but I've never had confirmation of it.
> Nah. It's just a spring loaded plunger sort of thing. When you (or
> your stove) depresses that little spindle on top of the canister it
> opens the valve.
Makes sense as a check valve would add another restriction to flow.
Ed Huesers
Http://www.grandshelters.com
John Decker
Just kidding Ed. I thought you were joking in your answer. Forgive my
Presumption!!
JD
John Decker
says...
>
>John Decker wrote:
>> The generation of self-serving methane flatulence in one of your ice
>> enclaves could potentially extend precious fuel and save the day.
>
>There is no methane in the flatus of many, if not most, adults.
>There is some hydrogen though.
>
Mr. Curl why don't you tell the complete truth...there is a genetic component to
consider. Its true that 2/3 of adults pass a mixture of other gases but about
1/3 of adults pass Methane gas mixed with hydrogen. According to Dr. James A.
Roth the author of Gastrointestinal Gas (Ch.17:Gastroenterology, V.4, 1976) ...
if both parents are methane producers, their children have a 95% chance of being
methane producers as well. Furthermore, Dr. Roth said Farts burn because they
contain methane (sometimes) and hydrogen, both of which are flammable gases.
Farts burn with a blue or yellow flame. A blue flame is indicative of the
presence of methane in the flatus.
JD
J. Curl
> > Ed Huesers wrote:
> >>Myself... I'll continue to look at the fuel system as a geyser,
> >>blowing gas back up the fuel line and all the way into the tank at times.
>
> J. Curl wrote:
> > Doesn't the pressure gradient in a geyser go from bottom (high
> > pressure) to top (low), exactly the opposite of an open inverted
> > canister of fuel?
>
> As soon as the liquid fuel touchs something warm enough to vaporise
> it, the pressure in that area is greater and it would blow the liquid
> back up the line until the gas cooled enough to turn back into a liquid
> state. The original gas could have been traveling fast enough that, with
> it's own momentum, it over shot the area in the generator where heat and
> vaporization would be in equilibrium and it would be an eruption back up
> the line or into the tank.
> Then, when the gas is pushing the liquid, there is also the momentum
> of the gas again, the gas will cool and cause a vacuum sucking the fuel
> down the line with even more speed and momentum.
> Normally, there are orifices in a fuel system to stop these surges
> but when approaching the extreme cold mentioned...
> Chris talked of moving the tank and it worked better. There may be
> high spots in the line where the gas has warmed the line enough and the
> gas doesn't turn to liquid but remains a gas pocket where the liquid
> won't flow over with just gravity.
Well Ed, as plausible as that might seem, it really isn't a description
of how a geyser works. More to the point, it doesn't explain why Chris
has experienced an apparent loss of initial pressure.
But it is a nice visual.
J. Curl
> J. Curl says...
> >There is no methane in the flatus of many, if not most, adults.
> >There is some hydrogen though.
> >
> -------------------
> Mr. Curl why don't you tell the complete truth...there is a genetic component to
> consider. Its true that 2/3 of adults pass a mixture of other gases but about
> 1/3 of adults pass Methane gas mixed with hydrogen. According to Dr. James A.
> Roth the author of Gastrointestinal Gas (Ch.17:Gastroenterology, V.4, 1976) ...
> if both parents are methane producers, their children have a 95% chance of being
John, if the "complete truth" includes all related facts then you
have also failed to present it. Why not mention that the text you cut
and pasted from some website does not necessarily comprise a consensus
on the subject of methane in human flatus. And what you quoted does
not state that there is a genetic component. Do you have another
source or was that just an assumption?
Far more troubling is your implication that Ed and his igloo inhabiting
friends are the spawn of methane producing parents.
Chris Townsend
<e...@grandshelters.com> writes
>> Ed Huesers wrote:
>>>Myself... I'll continue to look at the fuel system as a geyser,
>>>blowing gas back up the fuel line and all the way into the tank at times.
>
>J. Curl wrote:
>> Doesn't the pressure gradient in a geyser go from bottom (high
>> pressure) to top (low), exactly the opposite of an open inverted
>> canister of fuel?
>
> As soon as the liquid fuel touchs something warm enough to vaporise
>it, the pressure in that area is greater and it would blow the liquid
>back up the line until the gas cooled enough to turn back into a liquid
>state. The original gas could have been traveling fast enough that,
>with it's own momentum, it over shot the area in the generator where
>heat and vaporization would be in equilibrium and it would be an
>eruption back up the line or into the tank.
> Then, when the gas is pushing the liquid, there is also the momentum
>of the gas again, the gas will cool and cause a vacuum sucking the fuel
>down the line with even more speed and momentum.
> Normally, there are orifices in a fuel system to stop these surges
>but when approaching the extreme cold mentioned...
> Chris talked of moving the tank and it worked better. There may be
>high spots in the line where the gas has warmed the line enough and the
>gas doesn't turn to liquid but remains a gas pocket where the liquid
>won't flow over with just gravity.
This makes sense. When you shake a cartridge the flame often splutters
and flares as the gas comes out in surges.
>
>>>I've heard before that there is a check valve in the purchased
>>>canisters so one can't refill them but I've never had confirmation of it.
>
>> Nah. It's just a spring loaded plunger sort of thing. When you (or
>> your stove) depresses that little spindle on top of the canister it
>> opens the valve.
>
> Makes sense as a check valve would add another restriction to flow.
>
Chris Townsend
Chris Townsend
Curl <jhc...@yahoo.com> writes
I experience this initial loss of pressure with all cartridges and all
stoves at any temperature (most recently with a Primus Micron and GoGas
cartridge at 60F). With a new cartridge the gas comes out so fast that
it can blow the flame out and even turned down a little flames flow up
the sides of the pot. This doesn't last more than 5 minutes but in my
experience it always occurs, except with Powermax cartridges.
>
>But it is a nice visual.
>
Indeed.
Chris Townsend
Bill Tuthill
Why do you call that a Zdarsky tent? Your URL was for the Ski Guide Tarp.
> Step B) pull warm butane cartridge out of expedition parka internal
> pocket, attach to stove, and light.
Trouble is, when the butane cartridge gets low, it tends to frost over.
I'm not sure why it frosts more when low -- perhaps J Curl could explain.
This means that backcountryers accumulate hundreds of semi-used cartridges
in their garages, not wanting to take one and risk frosting-over and/or
premature loss of pressure in cold temperatures.
> Alternative B) pop the metal disk on the reusable Primus Heat Pad and
> place pad in cavity of inverted cartridge.
How does that work? I found pictures and references on the web, but none
explained why it is reusable. "Requires use of stove stand" one says.