Bushwalking gear and paraphernalia. Electronic gadget topics (inc. GPS, PLB, chargers) belong in the 'Techno Babble' sub-forum.

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TIP: The online Bushwalk Inventory System can help bushwalkers with a variety of bushwalk planning tasks, including: Manage which items they take bushwalking so that they do not forget anything they might need, plan meals for their walks, and automatically compile food/fuel shopping lists (lists of consumables) required to make and cook the meals for each walk. It is particularly useful for planning for groups who share food or other items, but is also useful for individual walkers.
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Re: Fire Maple gas canister adapter

Mon 16 Jan, 2012 8:15 pm

I agree Gas may be getting expensive however it is just so convenient and clean and whilst I love my SEVA 123(not the R) I do not like the volatility nor stench of Shellite now and since I acquired the FMS100T I am very happy with its performance even in -5c or a bit less owing to the canister inversion capability for liquid feed :)
corvus

Re: Fire Maple gas canister adapter

Mon 16 Jan, 2012 8:42 pm

I agree that gas is getting rather expensive and do wonder why :roll: But it is the fuel of choice for many reasons. I love my Optimus Nova + but the smell of the fuel and mucking around with simmering means I am a gas convert. And as Corvus writes, the ability to invert the cylinder means for most conditions in Tassie gas is more than adequate.

Tony will add that, hypothetically he well be refilling cylinders but not in real life :wink: I think it is illegal in the land of the endless bureaucrat but that might be just a fear campaign run by the gas cylinder suppliers.

Cheers

Re: Fire Maple gas canister adapter

Tue 17 Jan, 2012 5:04 am

Ent wrote:I agree that gas is getting rather expensive and do wonder why :roll: But it is the fuel of choice for many reasons. I love my Optimus Nova + but the smell of the fuel and mucking around with simmering means I am a gas convert. And as Corvus writes, the ability to invert the cylinder means for most conditions in Tassie gas is more than adequate.

Tony will add that, hypothetically he well be refilling cylinders but not in real life :wink: I think it is illegal in the land of the endless bureaucrat but that might be just a fear campaign run by the gas cylinder suppliers.

Cheers
Refilling is technically illegal here too, but I have (ahem) "a very close friend" who has been doing it for a couple of years with no problems. Brings the price for 220g down from about $6.00 to about $1.25. No issues thus far, but it takes a little bit of time.

HJ

Re: Fire Maple gas canister adapter

Tue 17 Jan, 2012 5:41 am

flyinglion2000 wrote:Jim I tried searching for a diagram or image of this feed tube so I can undertand it better. I googled quite a bit but to no avail. Do you have an image you can put up here? Where specifically is the "top". I am trying to determine if this feed tube is designed with the can operating in the horizontal position or in the vertical position. I would assume horizontal as that is a prevalent position of use for these types of cans (ie all those portable gas camping stoves that go for about $20+) at least here in Australia.

I played around with the Kovea Cobra and interestingly, the connection on the long can end is such that when its two legs are spread the notch in the collar of the long can is always uppermost (assuming a level surface). So presumably the boys at Kovea designed it that way with this situation in mind; that is when the can is horizontal with its nocth up the feed tube sucks gas not liquid.
It will vary a bit company to company, but this photo should give you an idea of what's going on:
Image

You're surmise is correct: the vapor feed tube generally aligns with the notch in the collar of the canister. If the notch is up, then the vapor feed tube sucks vapor. If the notch is down, then the vapor feed tube sucks up liquid. To get the flare you saw in my photo above, I simply rotated the canister to the right. That's the danger of the Kovea type adapter. THERE IS NOTHING TO PREVENT THE CANISTER FROM ROLLING and producing a sudden, unexpected, uncontrolled flare. I think I may post a warning on my blog. The Kovea type adapter is fine for upright use, but who wants to put a top-mounted stove up on one of those "long" 100% butane cans? Everyone wants to use them in side laying mode. Not a problem if one's stove is a) already hot and b) has a pre-heat mechanism, but absent either of those, your stove will flare. The stove in my flare photo was quite hot at the time of the flare but had no preheat mechanism.

HJ

Re: Fire Maple gas canister adapter

Tue 17 Jan, 2012 7:07 am

Ent wrote:I agree that gas is getting rather expensive and do wonder why :roll: But it is the fuel of choice for many reasons. I love my Optimus Nova + but the smell of the fuel and mucking around with simmering means I am a gas convert. And as Corvus writes, the ability to invert the cylinder means for most conditions in Tassie gas is more than adequate.

Tony will add that, hypothetically he well be refilling cylinders but not in real life :wink: I think it is illegal in the land of the endless bureaucrat but that might be just a fear campaign run by the gas cylinder suppliers.

Cheers


Hi Ent,

As pointed out refilling is illegal and should not be done, I do not encourage any one to refill canisters.

There are some very good reasons refilling canisters is illegal, if they are overfilled then they have the potential to rupture, if the canister is near naked flame when the canister ruptures then I would not want to be nearby.

Tony

Re: Fire Maple gas canister adapter

Tue 17 Jan, 2012 7:12 am

hikin_jim wrote:It will vary a bit company to company, but this photo should give you an idea of what's going on:
Image

You're surmise is correct: the vapor feed tube generally aligns with the notch in the collar of the canister. If the notch is up, then the vapor feed tube sucks vapor. If the notch is down, then the vapor feed tube sucks up liquid. To get the flare you saw in my photo above, I simply rotated the canister to the right. That's the danger of the Kovea type adapter. THERE IS NOTHING TO PREVENT THE CANISTER FROM ROLLING and producing a sudden, unexpected, uncontrolled flare. I think I may post a warning on my blog. The Kovea type adapter is fine for upright use, but who wants to put a top-mounted stove up on one of those "long" 100% butane cans? Everyone wants to use them in side laying mode. Not a problem if one's stove is a) already hot and b) has a pre-heat mechanism, but absent either of those, your stove will flare. The stove in my flare photo was quite hot at the time of the flare but had no preheat mechanism.

HJ


Hi HJ,

Thanks for the photo of the inner butane canister tube, I was unaware than it had a kink in it, the Coleman Max canisters have a flexible tube with heavy sintered bronze filter on the end.

Tony

Re: Fire Maple gas canister adapter

Tue 17 Jan, 2012 10:11 am

Tony wrote:As pointed out refilling is illegal and should not be done, I do not encourage any one to refill canisters.

There are some very good reasons refilling canisters is illegal, if they are overfilled then they have the potential to rupture, if the canister is near naked flame when the canister ruptures then I would not want to be nearby.
There are indeed some good reasons not to do one's own refills. The very good friend I referred to earlier only refills with butane which has a relatively low vapor pressure. Attempting to create propane blends ups the risks significantly.

Referring to my friend again, he always weighs the canister as he fills and keeps in mind the original weight that the canister was when it was first purchased. He usually underfills by a few grams, just to be absolutely safe.

Not something without risk if you decide to undertake refilling on your own. If you do decide to do it, be very methodical about how you do it.

HJ

Re: Fire Maple gas canister adapter

Tue 17 Jan, 2012 10:18 am

Tony wrote:Thanks for the photo of the inner butane canister tube, I was unaware than it had a kink in it, the Coleman Max canisters have a flexible tube with heavy sintered bronze filter on the end.
Similar items, but of course diametrically opposed in terms of what they do. The Coleman Max canister's tube was intended to point down and pick up liquid. The 100% butane canister's tube is intended to point up and pick up vapor.

The Max's canister is superior in that no matter which way you turn the canister, the tube always points down. The cheap butane canisters have a fixed tube. Rotate the canister, and you'll have liquid pouring into a burner designed for vapor feed only -- with "interesting" results. :shock:

HJ

Re: Fire Maple gas canister adapter

Tue 17 Jan, 2012 10:49 am

hikin_jim wrote:
Tony wrote:As pointed out refilling is illegal and should not be done, I do not encourage any one to refill canisters.

There are some very good reasons refilling canisters is illegal, if they are overfilled then they have the potential to rupture, if the canister is near naked flame when the canister ruptures then I would not want to be nearby.
There are indeed some good reasons not to do one's own refills. The very good friend I referred to earlier only refills with butane which has a relatively low vapor pressure. Attempting to create propane blends ups the risks significantly.

Referring to my friend again, he always weighs the canister as he fills and keeps in mind the original weight that the canister was when it was first purchased. He usually underfills by a few grams, just to be absolutely safe.

Not something without risk if you decide to undertake refilling on your own. If you do decide to do it, be very methodical about how you do it.

HJ


Hence my decision to rather put together a solution that permits me to directly attach long butane cans - with the obvious caution that the orientation of the can is critical to prevent "interesting" flare ups. Even though I plan to use the adapter on a stove with a preheat/generator tube, it is still going to be important to ensure that the stove gets a gas feed during start up. - That means either standing the can upright or keeping the notch up during start-up.

The end result should be to minimise my usage of propane/butane mix canisters - probably to about the same level as I would if refilling, assuming that each canister has a limited number of refills possible over its life. As a result, by an uneducated guess, I would hope that I would be purchasing roughly the same number of propane/butane canisters for my cold weather use as I would if I were refilling. The result will hopefully be safer and much less effort.

Re: Fire Maple gas canister adapter

Tue 17 Jan, 2012 12:33 pm

gmrza wrote: Even though I plan to use the adapter on a stove with a preheat/generator tube, it is still going to be important to ensure that the stove gets a gas feed during start up. - That means either standing the can upright or keeping the notch up during start-up.
Yes. Attend to that, and all should be well.

HJ
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