Author Topic: A quick question about Gas Cannisters  (Read 644 times)

quixoticgeek

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Re: A quick question about Gas Cannisters
« Reply #15 on: 21:15:02, 20/04/17 »
ive not had time to read all the thread,
i posted a video on here ages ago which caused a bit of a stir ... :D
ive been putting off posting it,
but what the hell, here it is together with a follow up video


ALL THINGS DONE AT YOUR OWN RISK...  :o
I can say weve had no problems with these adapters,


]https://www.youtube.com/edit?o=U&video_id=2T4WGGBc0Wk


part 2


https://www.youtube.com/watch?v=PerSkOSfhGs


Your first link is broken, I think you mean:


https://www.youtube.com/watch?v=2T4WGGBc0Wk


J
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Http://b.42q.eu/ - Beer, Bikes and Backpacking.

beefy

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Re: A quick question about Gas Cannisters
« Reply #16 on: 21:28:34, 20/04/17 »

Your first link is broken, I think you mean:


https://www.youtube.com/watch?v=2T4WGGBc0Wk


J
thank you ...  8)
43 wild camps last year 14 this year

quixoticgeek

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Re: A quick question about Gas Cannisters
« Reply #17 on: 21:57:49, 20/04/17 »
thank you ...  8)


Don't thank me too soon.


If you have a gas canister with 100% butane in it, that contains 220g of butane under pressure. And you decant that into one of equal volume, then you will get 110g in each canister. Cooling the bottom cyclinder do say -15C (totally doable with a domestic freezer), will increase this yield somewhat, but you're still going to get approximately half the gas in one, and half in the other. Either way, you're not going to empty the top cylinder into the bottom one, you can't push a fluid up hill (unless you have a Haskell pump). If you want to increase yield, you'll want to cool the bottom cylinder continually while it's filling (pressurisation will make it hotter). You can do this with an ice bath with salt added. But you're still going to get that pesky issue with pushing a fluid up hill...


This is before we get onto the issues with the fact that most of the dirt cheap bistro gas canisters are purely butane, which means that they don't work below about 10C (plus or minus), unless you have a remote canister stove.


In short: Nice idea, but the yield isn't quite as good as you would like.


J


Note: assumptions are made on volumns and pressures, and gas laws. YMMV
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Http://b.42q.eu/ - Beer, Bikes and Backpacking.

beefy

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Re: A quick question about Gas Cannisters
« Reply #18 on: 22:10:14, 20/04/17 »

Don't thank me too soon.


If you have a gas canister with 100% butane in it, that contains 220g of butane under pressure. And you decant that into one of equal volume, then you will get 110g in each canister.
this all sounds very clever,

why do i end up with one full cylinder and one empty cylinder then?
also the temperature doesnt matter to me, i do have a remote cylinder stove, with a pre heating tube for the gas,



43 wild camps last year 14 this year

Snowman

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Re: A quick question about Gas Cannisters
« Reply #19 on: 09:55:40, 21/04/17 »
Quote
I think that the general assumption by MSR is that if you're that far off the beaten track, then you use a liquid fuel stove, be it the MSR Whisperlite internationale, or one of their jet engines like the Dragonfly or XGK. These burn pretty much every liquid fuel known to man (apart from meths). So where ever you are you should be able to find something to burn (those places that cook on gas probably use kerosene for lighting).[/size]Oh, and this is before we take into account that gas can suck below 10C


Firstly, I would make the point that the subject of this thread is 'A quick question about Gas Canisters', which is why I made some points regarding Gas Canisters.   While I accept that liquid fuel stoves have their place (I own both), they are usually considerably more expensive than gas ones and are not anyway, the subject of this thread.


In fact my original post was simply pointing out that what you call 'threaded' canisters are also very expensive when compared to what you refer to as 'Camping Gaz' (which is just a brand name for what I would refer to as a standard canister).    The fact that these canisters are available in countries where the threaded variety are not, was mentioned as a bonus feature, not the be all and end all.    I am simply pointing out that getting an adaptor with a gas stove provides greater flexibility than relying on threaded canisters and is cheaper to run.    As to safety, I've never had a problem with using an adaptor.


If MSR have consciously set a marketing strategy out of making their stoves incompatible with standard canisters, with the objective of getting people to buy their much more expensive product, then having had dealings with marketing people in the past I know that it is entirely possible.   However that (IMO) would be a somewhat short-sighted strategy since, as Quixoticgeek pointed out on this thread, a stove that relies solely on specifically threaded canisters may not even work in parts of Western Europe.    I guess it is also possible that other brands of adaptor will fit their product so they can't be bothered.