Bushwalk Australia

As winter approaches, those of us that use gas would be wise to keep our cannisters warm.

The method I have used for a while now is to place my cannister in a titanium bowl of warm water as shown in this post.
http://bushwalk.com/forum/viewtopic.php?f=15&t=635#p69050

This is fine when you're cooking alot, but if just boiling a quick cuppa, its hardly worth the effort. Came across the alpine BOMB today, so I might give this a shot. (B loody Outrageous Mountain Burner). Its basically a foam wrapped around a gas cylinder and gaffe taped up. then a copper tube is inserted in to exchange heat from the flame into the cannister. Marvelous!





details outlined here: http://www.ademiller.com/blogs/climbing/2005/12/gear-the-alpine-bomb.html
Does anyone have any other ideas to keep the cannister warm?

Hi Ninjapuppet,

You have brought up an very important issue, keeping canisters warm, save me repeating a lot of things Roger Caffin's FAQ has a lot of very good information on stoves in general, fuel mixtures and liquid vs gas feed etc, there is a very good explanation why liquid feed gas canister stoves do not suffer from latent heat of vaporization. When I used to do winter trips with upright canister stoves I used to place the canister inside my sleeping bag of jacket for a while before use, these days I use my Coleman Extreme or my little myog remote canister stove, which I have used around -15ºC to -20ºC with no canister warming and for testing purposes I have used canisters that have been in the freeze at -20ºC with no problems. I would not use a liquid feed canister at much below -20ºC.

The reason a upright canister stove can work at high altitude in fairly cold conditions is because the pressure outside the canister is low, what happens inside the canister is not influenced by the pressure outside the canister, the volume and temperature are important.

For colder than -25ºC shellite stoves are more suitable.

The BOMB is a very nice design, a very interesting article, I have seen copper wire twisted around the canister to do the same thing. I am not sure why they could not use the MSR WIndpro in the cold, I am guessing that they did not use it in liquid feed configuration.

But remote liquid fed canister stoves are difficult to hang.

A long time ago I designed a liquid feed gas canister stove that could be hung, I only got it to the concept/prototype stage before moving on to other projects.

Tony

I use an upright system for winter camping in the California mountains. Typically temperatures are -15 to -5 Celsius and I find that I can keep things going with a simple aluminum windscreen.

Not that it matters, but the cooling in upright canisters isn't only due to the energy required to vaporize the liquid fuel (latent heat), but also because it takes energy to expand the gas. But vaporizing the fuel is about 90% of it.

Tony, if that prototype of yours were a finished product I'd buy one in a second.

Orion wrote:Tony, if that prototype of yours were a finished product I'd buy one in a second.

Hi Orion,

I might look into doing some more development on the system, but as for making some for commercial sale, I have looked into this and it is all to expensive and difficult.

Tony

G'day Tony,
Send it to Fire Maple or Bulin who knows they may just well take you up on it
corvus
P.S. sorry forgot to say nice design

corvus wrote:G'day Tony,
Send it to Fire Maple or Bulin who knows they may just well take you up on it
corvus
P.S. sorry forgot to say nice design

Hi Corvus,

Thanks, I will do a better a version and then think about sending the design in.

Tony

ninjapuppet,

That looks like a fairly practical design. Might even be lighter than carrying sufficient wire to wrap around the canister, and it seems like less hassle than trying to get a copper wire to stay in contact with the canister from wrapping alone.

I worry that the canister might overheat. I suppose it's no problem though provided that you touch the canister fairly frequently with your hand.

I also wonder if the hot copper wire might melt the tape or cause a fire. Have you used it a lot?

HJ

P.S. Brilliant design on the upright liquid feed stove, Tony. Not try to slight it by not mentioning it. It's just that you've shown it to me before, so you already know I think it's brilliant.

hikin_jim wrote:P.S. Brilliant design on the upright liquid feed stove, Tony. Not try to slight it by not mentioning it. It's just that you've shown it to me before, so you already know I think it's brilliant.

Hi HJ,

I have spent some time today working on my JetBoil hanging stove project which incorporates that early design concept, I will post finished stove soon.

Tony

Something even more polished than before? I look forward to that!

HJ