Need to refill small gas cylinders?

[Strider]

How heavy is the offending canister MD?

[Moondog55]

Spot on the normal weight, I weighed it before filling and added 100grams of gas as which point it had stopped filling. This was one of the empty canisters I rescued from PV hut so I don't know its history but looked perfect from the outside
I will decant the contents into one of the empty MSR canisters tho
I'm not prepare to take a chance on this
Took the pix inside but transferring outside of course

[hikin_jim]

That canister bulge is very strange. I'd definitely get the gas out of there; it can't be safe. Canister bottoms are supposed to evert (i.e. pop outwards) before failing, although I've never heard of one doing it in one odd spot.

The problem with canisters that you don't know the provenance of is that you don't know how old they are or how long they've been sitting or in what conditions. I usually only refill canisters that appear in good based on a visual inspection, and I typically only refill canisters that I bought new myself. I once refilled a canister that I had found in the ruins of an old tavern/hostel up in the mountains. God knows how long it had been sitting up there. Well, after I filled it, I heard a sudden pop, then the hiss of gas, and then the mercaptan smell that comes with gas. Fortunately, I wasn't near any flame or electric arcs or anything that might ignite it. I set it down in the middle of a concrete pad and let it hiss itself to emptiness. Thereafter I decided to only refill good looking canisters that I myself had bought new.

HJ

[hikin_jim]

Very true Jim. I've never had any problems at altitude or in extreme cold with my stoves or canisters (and I've used some dodgy looking Chinese things in the past). The attached pic was well over 7,000m and later that night, at around 1am, I boiled 2L water with an outside temp in the order of minus 40 dgrees C. If they didn't work reliably at altitude not many would be climbing the 8,000m hills

-40°C! Ohmigosh, now that is COLD. I'm actually a little surprised that it worked in those temperatures although if you started with a warm canister and had a decent amount of propane in it, then it makes sense that it would work. -40°C just has such shock value.

What peak were you climbing at the time?

HJ

[horsecat]

Yep, it was a tad chilly so the canisters lived in my sleeping bag when not in use.

That pic was from Muztagh Ata in far western China. Very cold hill that one, in fact some say it can be colder than Everest due to its more northern longitude, plus the Siberian winds that blast it from the north east. The temperatures we experienced on summit day were enough for people to suffer severe frostbite and sadly even kill an individual. Despite having the best altitude boots and OR mitts I very nearly had issues of my own (spent about an hour with my feet and right hand shoved into a Pakistani man's armpit back down at Camp 3 to warm them up as they were like wood and going white). MSR Reactor stove worked great though

[andrewbish]

Yep, it was a tad chilly so the canisters lived in my sleeping bag when not in use.

That pic was from Muztagh Ata in far western China. Very cold hill that one, in fact some say it can be colder than Everest due to its more northern longitude, plus the Siberian winds that blast it from the north east. The temperatures we experienced on summit day were enough for people to suffer severe frostbite and sadly even kill an individual. Despite having the best altitude boots and OR mitts I very nearly had issues of my own (spent about an hour with my feet and right hand shoved into a Pakistani man's armpit back down at Camp 3 to warm them up as they were like wood and going white). MSR Reactor stove worked great though

*&%$#! hell! What an experience! I have some interest in this mountain. Will send PM

[hikin_jim]

That pic was from Muztagh Ata in far western China.

Would you mind if I posted that photo on my blog? I mean it is the perfect illustration to refute the claim that "gas stoves don't work at altitude."

HJ

[Moondog55]

I'm wondering if I should take this in to MD and have them send back to JetBoil to see if there is a batch problem with this run of gas canisters. Sounds interesting horsecat; how technical is the climbing?

[Gadgetgeek]

I wouldn't worry too much about it. probably just a defect in that particular one, possibly brought on by a temp change during the gas transfer. I wouldn't use it, but I also wouldn't worry about trying to send it in. I doubt anyone would do much with it.

[hikin_jim]

I doubt anyone would do much with it.

They'll probably just chalk it up to "refilling is an improper use of our product" and dismiss the issue.

Rather odd, but what can you do? Just drain the gas and use a different canister I suppose. Perhaps it's best to recycle the offending canister.

HJ

[Moondog55]

I have done that drain into another canister and the offending one is in the freezer waiting to be punctured
Mind you I'd not have mentioned "Re-Filling"
There is such a huge mark-up on the small canisters I'll keep on re-filling tho

[horsecat]

PM sent Jim.

I'm wondering if I should take this in to MD and have them send back to JetBoil to see if there is a batch problem with this run of gas canisters. Sounds interesting horsecat; how technical is the climbing?

Nope, no technical climbing bits on Muztagh but the altitude, cold, deep snow and big load carries makes up for that though. A good training ground for something bigger and meaner

[Tony]

It should be pointed out that refilling gas canisters used with bushwalking stoves is ILLEGAL IN AUSTRALIA AND SHOULD NOT BE DONE

If you overfill a canister it can be very dangerous, which is what I suspect has happened to the damaged cylinder that Moondog55 has posted a photo of, that canister should be emptied, punctured and disposed of so it cannot ever be used again.

Tony

[Strider]

Here come the fun police!

Tony I suggest you read MDs post re: overfilling.

[Moondog55]

No need to shout Tony, it's bad manners.
We are almost all adults here and able to make reasoned decisions without the interference of government and the fun police

[Tony]

Here come the fun police!

Tony I suggest you read MDs post re: overfilling.

Hi Strider,

As an engineer I fully understand the the physics behind filling a canister with with volatile gases, and the dangers of an overfilled canister, there is a reason why it is illegal to refill a canister and it is obvious some people should never try it.

Can you explain to me where the fun is in an exploding overfilled gas canister.

Tony

[Tony]

No need to shout Tony, it's bad manners.
We are almost all adults here and able to make reasoned decisions without the interference of government and the fun police

Hi Moondog55,

Bad manners or fun police or what ever, I do not care if you do not like my warning post, as mentioned in my post to strider where is the fun in an exploding overfilled canister, by the photo's that you posted and your fun police comment it is obvious that you have very little understanding on the dangers of overfilling a canister, I would suggest you do some more research into refilling canisters before you blow yourself or somebody else up. There is a reason it is illegal to refill a canister.

Tony

[whitefang]

No need to shout Tony, it's bad manners.
We are almost all adults here and able to make reasoned decisions without the interference of government and the fun police

Hi Moondog55,

Bad manners or fun police or what ever, I do not care if you do not like my warning post, as mentioned in my post to strider where is the fun in an exploding overfilled canister, by the photo's that you posted and your fun police comment it is obvious that you have very little understanding on the dangers of overfilling a canister, I would suggest you do some more research into refilling canisters before you blow yourself or somebody else up. There is a reason it is illegal to refill a canister.

Tony

Correct me if I'm wrong Moondog, but it does seems like you have an understanding of the dangers of overfilling a canister.

I don't see why it should be an illegal practice considering it is legal elsewhere and there are ways to do it safely. It's a good way to save a few dimes and I'll no doubt be doing it when I have a few empty canisters lying around.

[Strider]

Here come the fun police!

Tony I suggest you read MDs post re: overfilling.

Hi Strider,

As an engineer I fully understand the the physics behind filling a canister with with volatile gases, and the dangers of an overfilled canister, there is a reason why it is illegal to refill a canister and it is obvious some people should never try it.

Can you explain to me where the fun is in an exploding overfilled gas canister.

Tony

One need not be an engineer to understand the risks of filling canisters. People will do as they please and they certainly don't need you treating them as though they are completely clueless. If MD does manage to "blow himself up", that is his prerogative.

[Moondog55]

All other risks aside overfilled canisters do not 'explode" they rupture; and there is a huge difference.
The devices I use to refill are made in the same place that the canisters are
The rule against refilling isn't IMO opinion a safety rule; it is to ensure profit maximization by the canister importers; the inherant dangers are no greater than refilling the petrol tank of your car

BTW Where did I ever say I had overfilled? It is almost impossible to overfill using the tools available, Boyles law and all that and given the characteristics of butane i think I'd rather deal with a butane BLEVE than a Shellite one and there is certainly no law against using Shellite although there are many common sense rules for safety reasons.

[Orion]

Cool photo, Moondog! DId you see or hear this happen?
What is it supposed to look like when the bottom bulges out?

Does anyone have a photo or a link to a photo that shows (another) one of these canisters with a bulging underside?

[Moondog55]

It looked perfect after I filled it Orion, spot on weight [ my scales are accurate to 2 decimal places] and I never heard anything. My conjecture is the this canister was overheated when cooking in the hut and the owners simply left it behind rather than do the right thing and take the damaged canister back with them.
I rescued 6 of the Jetboil canisters from PV hut, including my own 2; this is the only one that looks like this after refilling.
It certainly isn't an overheating while in storage issue as the storage area never gets hotter than ~ 30C, being well ventilated and insulated

[madmacca]

It should be pointed out that refilling gas canisters used with bushwalking stoves is ILLEGAL IN AUSTRALIA AND SHOULD NOT BE DONE

If you overfill a canister it can be very dangerous, which is what I suspect has happened to the damaged cylinder that Moondog55 has posted a photo of, that canister should be emptied, punctured and disposed of so it cannot ever be used again.

Tony

Tony,

There are indeed dangers in overfilling gas cannisters. But a careful reading of Moondog's post shows that he is not overfilling. There are also dangers in filling cannisters with gases other than that which they were designed for (especially those with different vapor pressures).

Given these dangers, it is quite appropriate that the law disallows it. But it doesn't mean that careful and well informed people can't do it safely. And this thread (and a couple of similar ones) is about making people better informed.

I'd suggest that what this episode has exposed is the dangers of (re)filling gas cannisters of dubious provenance and history.

[Mark F]

While I don't suggest anybody refills a canister, I am yet to find a law/regulation that provides a penalty to an individual for refilling a "non-refillable" container. I expect there are penalties to businesses and organisations who do this, or to individuals who sell refilled containers. Perhaps we could revert to the quite dangerous original Bluet puncture type canisters to make sure nobody ever refills one.

The words are there to protect the manufacturer from potential law suits and to indicate that the item has not been tested in situations where it has been refilled. It's similar to "do not cook in your tent" or the lack of "food grade" labelling on some silicones - not because they are necessarily dangerous to human health but rather the manufacturer didn't pay lots of money to have the testing done.

[hikin_jim]

I was thinking about the dangers of refilling canisters. First let me say that I neither encourage nor discourage anyone to refill canisters that are designed to be single use, disposable canisters. But just for my own edification, what are the dangers? Off the top of my head, I thought of the following:
1. The canister is old, the walls, seams, or valve have deteriorated in some fashion, and when refilled, the canister bursts. I should note that a burst canister could catch fire and or explode although I've seen cases where they did not. Never the less, even a bursting canister has a bit of force; see below photo. Note: The below is not my car. Thank you.

2. The canister is overfilled, and the canister bursts. Again, refer to the above photo.
3. The canister is filled with a fuel mix with a greater vapor pressure than the canister was designed for. Example: A canister originally filled with an 80/20 mix of isobutane/propane is filled with 100% propane. The canister bursts.
4. During refilling, fuel leaks and by one means or another catches fire. This could get very, er, interesting very quickly.
5. The canister valve is old and fails to function on a trip, leaving you with a dead weight in the middle of the bush. While typically not fatal, it certainly isn't desirable.

That's just off the top of my head. Are there others that I'm missing?

HJ

P.S. Hi, Tony, nice to "see" you around.

[Orion]

What happened to that car?

Does anyone have a photo of a bulging or burst canister?

[hikin_jim]

What happened to that car?

The individual left a canister of gas in the back window on a relatively hot day. Solar radiation heated the canister beyond the canister's capacity to withstand the resultant pressure. The canister burst.

Note that there is no blackening, charring, melting, or other signs of heat. In other words, this was just a burst and not an explosion.

As for a bulging canister, see some of the earlier posts in this thread.

HJ

[Orion]

The only bulging or burst canister photo I see in previous posts is Moondog's. It's the first and only photo of a bulging canister I've ever seen. How do you guys know that the way his started to bulge is unusual unless you've seen a few others that looked differently?

[Moondog55]

This is a first for me which is why I posted the picture
The base is normally a smooth hemisphere as are almost all pressure vessels including wine bottles

[Gadgetgeek]

I'm just going to toss in that the car looks far worse than the actual "force" might indicate. It doesn't take that much force on a very small area (ie, a burst cannister's wall being forced out at high speed) to cause tempered glass to shatter. The force coming from the inside, and the "puff" of the gas would push enough glass out of the hole to make it seem like it was all blasted out, but it wouldn't necessarily have been much more than enough to break the glass.
Personally I think that these cannisters are far safer to fill than the old CO2 cannisters I used to fill which had to be treated very carefully, and those were designed to be filled.