Jetboil

“I am very interested in these results. And how they were achieved.

I was inthe ADK in 0 degrees. The cansister was in my bag all night.


the morning boil for oatmeal and coffee took for freaking ever.


I carried the cansiter in my chest zip pocket all day. The 12:00 boil for cp o soup went okay.


For the evening meal boil we kept alternating canisters. As one would cool we'd throw on a fresh warm one. After the meals were prepped, then we put the canisters under the bag of food as it rehydrated. That warmed it up.



Question re your statement earlier:

"lee, that have to say that or some idiot will make a shield that is too tight and blow themselves up.”


the plastic cup must be pretty close around the canister. What are we worried about blowing up here??


that is .. .can the canister be tightly encased (in the plastic cup with hot water) but the flame is still free.


Is it the flame we're worried about (e.g. don't put a windscreen so tightly around the flame that it . .. .(that it what???)


What happens with canister gas that causes it to blow up? Myabe that's the basic question I need an answer to. What causes cansisters to blow up, and how is the wind screen different from the enclosed cup and hot water in that regard.



I loved the jet boil's wieght/convinence/small packsize etc. The long long boil at zero degrees kind of stunk.”

“Gas go boom.”

“realizing you are being facetious.


However.


What exactly causes canister gas to go boom.”

“Glad you got the joke. :-)

Anyway, with any closed container that holds gas - canister, 1 lb propane canister, 20lb propane container for your home grill, whatever - as it gets warmer the gas inside will expand. Expands too much it will eventually break open at the weakest point. Some propane containers have a pressure relief valve, but not the small canisters for the backpacking stoves. Even if it did - it would produce a nice fireball as the pressure escaped. So, too much heat make gas go boom.”

“okay.

So far so good.


now. What causes the gas in the cansister to heat up and expand.


That is: A tight wind screen that encloses the flame source.

and/or a tight plastic cap that has boiling water in it . ..but does NOT block the flame source???”

“lee

with any stove - some of the heat is lost to the surrounding air through convection.

a tight windscreen can trap that heat and effectively heat up the canister.

this can be good if done right - by keeping the canister from getting too cold.

it can be overdone though, and heat up the canister too much - then boom!

this is not as much of an issue with the jetboil b/c as you know, it's very efficient (very little heat lost to surrounding air, i.e., very little heat available to be used to warm the canister)


this all very different from placing the canister in the hot water cup b/c the water is only about 200 deg. (and falling fast)- not hot enough to blow up your canister, but plenty hot enough to keep that sucker workin great.


if you want to be safe, don't boil those 2 oz. of water. just heat up the 2 oz. to say... 100-150 deg or so.
last edited: 12/15/04 12:41:14 PM”

“make sense?”

“This is all pretty solid beta, but I'll have to see it in action.

I must admit that the Whisperlite + fuel tank + stand + cutting board to set it all on get pretty heavy.”

“Let me say . .since I didn't before . .

I am pretty pysched about your experiement.


As I indicated, I had a tough time with the stove at 0 in the ADK a few weeks ago. I was pretty discouraged, but didn't want to give up on what I saw as a major stride in packing efficiency.

So. Thanks.”

“glad to be of service lee.

as the winter progresses and the temps get colder i'm going to continue to experiment and see just how effective the "hot water insulation" is.

i'll post any results.”

“great opportunity for testing this morning.

it was -10. repeated last test - great results.

time to boil - 3:00

after the 3 minutes, the water surrounding the canister had cooled to about 70*

it could get ugly at -20 or so. more tests to follow, as mother nature permits...”

“That's pretty good, Sacco.”

“cool”

“Good info.”

“yes, very good info. I'll give it a try next time I'll camp in the cold.”

“ditto.. about what gem said”

“Pot support & stabilizer will be available in May.

http://www.jetboil.com/Products/Accessories”

“now THAT will be cool. That pot support & stabilizer I mean.
last edited: 4/04/05 8:54:37 AM”

“I doubt it would. But then again you would primarily want the support so you can cook with the stove, so you wouldn't want the thing at full blast anyway.”

“yeah...I deleted it after I realized how stupid my question was. lol

now I need to go and check the weight of the stabilizer and pot support... well, the total weight of it all.”

“lol, gem- you gotta stop editing so fast - or start editing faster before someone replies to ya.

makes reading a thread confusing! :)”

“I know, I know... I edited it and took a pee break. :( I won't do it again.

but can you tell...I really, REALLY love the "edit" feature. REALLY!!!
last edited: 4/04/05 9:08:40 AM”

“maybe you should put a note at the end of every post that says

"Caution: wait 10 minutes to reply"”

“This post will self-destruct in 30 seconds.

8D”

“LOL

ya, yours is better zac”

“damn, I swear I posted on this thread and called you all buttheads...
wtf??”