I had the same problems, ended up warming the cylinder in the sun for a while, and putting cannisters in the freezer.. Worked well...
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I had the same problems, ended up warming the cylinder in the sun for a while, and putting cannisters in the freezer.. Worked well...
I bought two of those dodackies & neither will screw in properly, useless
I don't understand why you would do this?
Surely the canisters are a mix of butane and propane to work at altitude, but you don't get that mix from LPG.
Anyone got a link to a recommend filling adaptor?
so where do you get your hands on one of these? and maybe not a total cheap arse one but medium quality?
cheers
Ok so I never had much luck with my one as it wouldn’t thread into the LPG cylinder enough so gave up on it.
Then today I stumbled upon this and have ordered one, will report once I’ve tried it. https://www.mtn.co.nz/product/gas-ca...refill-adaptor
Hi guys, I haven’t read though the whole thread but can I suggest you put the empty can in the freezer before filling. (Stuff moves from hot to cold) law of physics. And yes the full bottle needs to be upside down to get liquid out. Be very careful not to over fill as it needs space to expand.
Refilling camping canisters with LPG is extremely dangerous. There is a very good reason LPG and 100% Propane are stored in heavy steel vessels.
DO NOT DO WHAT THESE GUYS ARE DOING!
There are 3 main gases we use for cookers. n-butane, Isobutane and Propane. They all have different properties and we use them in different situations.
The boiling point of the gases are:
n-butane = -0.4C
Isobutane = -11.7C
Propane = -42C
As you increase the gas temperature above the boiling point of the gas the pressure inside the canister rises. At 20C n-butane is still pretty harmless and can be contained inside a plastic Bic lighter, you could not do this with 100% Propane. Have you ever seen one of those green steel gas canisters that Coleman makes? That's 100% Propane. That is what is needed to contain that gas.
So n-butane is no good for our needs and 100% Propane is no good due to the heavy steel vessels we would need to contain it. What we use is a mixture of Isobutane ( a chemically rearranged n-butane which lowers the boiling point) and Propane. A lot of gas canisters don't list the mix ratio anymore but it's around 80/20.
LPG in New Zealand is typically 60/40 Propane and Butane.
What happens when you fill a camping canister with LPG and your pot of boiling water overflows onto the canister below? Or you use a windshield around your cooker? These canisters are not designed to withstand the pressures of the higher ratio of Propane. You are literally risking your (or whoever is near the stove) life doing this guys. Youtube has some examples of what a camping canister explosion looks like - Do you really want to risk it?
The only way you should refill your camping canisters is with the same blend of gas it originally had in it. Since most manufacturers don't list the blend anymore the only real way to minimise the risk is to transfer from the same brand to the same brand eg. MSR to MSR. It's generally cheaper to buy gas in the larger bottles so this really the only reason to be doing this, or you want a custom amount inside a canister instead of two small ones you could take a 3/4 full larger can and save on the weight of the can material.
The correct way to do the gas transfer is to weigh your empty canister first and record the weight. Say it was a 230g canister and the empty canister weighed 150g. You would fill the canister until it weighed 150+230=380g this is the safe amount. Do not overfill. Put your donor canister (of the exact same blend of fuel) in warm (NOT hot) water and your receiving canister into an ice bath. Once the donor canister has warmed up you invert it and using the adapter you start to fill the receiving canister which is still in the ice bath. Let it fill for a minute or so and then weigh the receiving canister. Repeat until you reach your safe fill value. If you exceed the safe fill value vent the excess off outside or use a stove to burn it off.
I can post some links to further reading and a suitable adapter if anyone is interested to learn more. I would recommend any of you that have filled your canisters with LPG to vent them off.
Here's a picture taken from Kiwicamping website showing some typical vessels for the gases mentioned. Note the LPG and the 100% Propane are in heavy duty steel vessels.
Attachment 135432
Here's a video showing how camping style canisters are manufactured and tested. Note how they are tested in 52C water. Take a look on a canister some time it will state do not use them above 50C for Isobutane. https://www.youtube.com/watch?v=81lwc0L8Tfw
And finally a report of someone being injured by using a windshield around a gas cooker ( Can only assume it was regular Iso/Butane mix gas). The likelyhood of this happening is greatly increased with a higher percentage of Propane. Don't let it be you, your family or friends for the sake of saving a minimal amount of money.
https://worksafe.govt.nz/topic-and-i...burn-injuries/
gentlemen -this bloke obviously knows his stuff .having read it his advice is definitely cheaper than an undertakers bill and the bill for the post match function (he cant be here but deep down hes a nice guy so drink up and have another on him) so Im firmly in his court.
BTW I also have a long standing aversion to things that can bite me or inflict pain -gases and electricity are top of the fucking aversion list.
LPG (propane) gas cylinder-bottle pressure chart
Temp Temp Pressure Pressure Pressure
ºC ºF kPa PSIG Bar
70 158 2482 360 24.8
60 140 2013 292 20.1
54 130 1794 257 17.9
43 110 1358 197 13.6
38 100 1186 172 11.9
32 90 1027 149 10.3
27 80 883 128 8.8
16 60 637 92 6.4
-1 30 356 51 3.6
-18 0 152 24 1.5
-29 -20 74 11 0.7
-43 -45 0 0 0
Note: Some numbers have been
It's an example of how explosions and injuries happen. Most of us have used windshields with upright canister stoves before and got away with it. Using LPG inside a canister increases the likelyhood of an explosion by lowering the temperature at which it will explode. That's the takeaway.
A chart of Propane pressures means nothing because we don't know at what pressure the canisters will explode. They are tested with a certain mixture of gas at say 52C and labelled not to be used above that temperature. Putting a different mixture of gas in there invalidates that test.
I was going to put a pt for butane up as well but having trouble getting a screen shot from my phone to my tablet.
The pressure at 30 deg isn’t much different.
It’s illegal to refill a disposable cylinder but most will cope with either gas pressure.
The work safe report says the stove fuel was LPG but the gas canisters was butane.
What was it?
The only learnings we can take from it is don’t use portable stoves if you are an idiot of work for worksafe.
Ok.
If you are gonna be so cheap you have to look for ways to squeeze the gas, maybe you have bigger problems..... most of the time I'm using Hexi or Meths, cheaper than gas by the way...... so the gas canister thing isn't a bugger for me, occasionally go gas cause I've got shitloads of canisters.
Is this whole refill canisters thing about being cheap? or not knowing how much you have left?. Both problems solved by changing your fuel methodology. Or carrying two canisters if no 2.
In the mornings I generally heat water till just hot to touch then disconnect and put the can of gas in the warm water for a couple of min and reconnect and continue cooking.
My issue is keeping the gas warm enough to supply enough pressure to the cooker especially as boiling off liquid has a refrigerant effect, I dont hunt in +30c temps tho and YMMV.
That's called evaporative cooling Cam, you might see that as ice forming on the outside of the canister sometimes even if the ambient air temperature is not below freezing. You've sussed one of the ways around it with sitting the canister in the warm water. The other way is using a stove that can handle liquid feed and inverting the canister.
Yup. If he had of read the manual (yeah right) he would have seen there is a maximum safe diameter pot/pan to be used on those cookers for that exact reason. A large amount of people over the world have been seriously injured or killed with those types of stove. They actually have two safety features - there is an automatic "disconnector" that will push the canister back at like 70-80PSI and then if the can continues to increase in pressure at something like 200PSI the can itself has small holes around the top called "Rim Vent Release/RVR" that will rupture and dump the gas. Unfortunately sometimes the first stage doesn't work properly and when the second safety goes and there's still a flame present it explodes.
I won’t mention how my mate warms a can up as K95 will have a heart attack :D I just chuck mine in my sleeping bag at night if I’m camping somewhere cold.
Get one of these https://www.mtngear.nz/product/gas-c...refill-adaptor $10 great for using up all those half/ quarter full cans you have lying around, and you can buy the large size ones and decanter into your smaller ones, save a few $$
:D I've seen some inventive ways. I'm not trying to be the fun police I just think there is a genuine ignorance of the risks with most people.This thread has over 15,500 views and no one had pointed out it's not a bright idea. We're all clued up about reloading and safety around that, our gas cookers are probably the only other thing we take with us in the hills that could explode. You're only going to be better equiped to make your own decisions around them if you learn a bit about them.
This could have the making of a Darwin Award if not careful?:o
It seems to me that we have more incidents with improper use rather than refilling.
I agree with @R95 that a warning should be given to anyone considering refilling, I’m just not sure you can stop some people hurting themselves.
Attachment 135681
These type had an issue some time back where you had to turn the top over (it was turn upside down for packing) before use otherwise it blew up.
Having any fuel under pressure near a flame is asking for trouble.
Absolutely agree with you 2post. Refilling seems to have just become a "thing" recently though. As long as I've thrown out some info for people to consider I've done my part.
Some good visual data on the gases here. Note at 30C (90F) 100% Propane has 5 times the vapour pressure of 100% Butane and the difference increases with higher temperature: https://www.engineeringtoolbox.com/p...ix-d_1043.html
And an interesting video showing a couple types of valve systems: https://www.youtube.com/watch?v=lpJQ5V6PQ4k
I'm gonna leave it at that people, better livin' .
We dont get 100% propane tho do we, its about 60/40 for lpg?
Yes we do, refer to the post I did a page back. "LPG" the stuff you buy for your BBQ in New Zealand is typically 60:40 Propane/Butane. Pause that video I posted at 0.57 and have a look at that chart in the background. The top line is 100% Propane, the bottom is 100% Butane. The ones in the middle are mixes and Isobutane. Should be clear what I'm getting at. It's all there for you now, make your own minds up. I really am gone now.