Previous :: Next Topic |
Author |
Message |
HitTheTrail Member
Joined: 30 Oct 2007 Posts: 5455 | TRs | Pics Location: 509 |
This valve for transferring gas between your backpacking stove canisters may already have been discussed here but I could not find it in a search so here goes. It is a valve with two Lindal thread openings so you can safely move gas from one canister to another. This is handy if you have a bunch of half used canisters and want to move the gas to make a full one. Also, it will allow you to use the larger 500g canisters at a fraction of the gas cost of a 100g and just keep filling the smaller canister after each trip out. You can even use the cheap off brand name large canisters at supermarkets like Fred Mayer to lower your gas costs. I am sure the gas is just as good.
The gadget is called a G-works gas saver($21) or gas saver plus($32). The gas saver plus has a fancy button on the side to release gas vapor in the canister being filled but I am not sure it is worth the extra money. There are tons of them for sale on ebay but I would recommend getting one from Amazon to insure the quality. Also, check out the other Lindel valve adaptors listed on Amazon.
Valve Lindal Valve Transfer gas
|
Back to top |
|
|
Riverside Laker Member
Joined: 12 Jan 2004 Posts: 2818 | TRs | Pics
|
Do you heat up the full one, and cool the empty one, to get more fuel in there? Might as well take advantage of the ideal gas law.
|
Back to top |
|
|
HitTheTrail Member
Joined: 30 Oct 2007 Posts: 5455 | TRs | Pics Location: 509 |
The company that sells the thing is an instruction free zone but I listened to some vids on youtube. They all said to put the bottom canister in the freezer for an hour or so and put the top one out in the sun for the same length of time. Some also said to just turn the valve on and go to bed and it will eventually fill. I didn't do either and it seemed to fill ok. It makes a big difference what the differential is between the two gas volumes.
|
Back to top |
|
|
Randito Snarky Member
Joined: 27 Jul 2008 Posts: 9512 | TRs | Pics Location: Bellevue at the moment. |
|
Randito
Snarky Member
|
Mon Oct 31, 2016 7:37 pm
|
|
|
HitTheTrail wrote: | This is handy if you have a bunch of half used canisters and want to move the gas to make a full one. |
Have you had much success with actually doing that? -- from reports I've read about refilling 1lb propane tanks from bulk propane tanks that getting the 1lb tank about half full is about as far as it goes -- even with putting the empty tank in the freezer overnight.
|
Back to top |
|
|
Malachai Constant Member
Joined: 13 Jan 2002 Posts: 16092 | TRs | Pics Location: Back Again Like A Bad Penny |
Good luck guys, I draw the line at refilling disposable cylinders. Like my house and hair too much. as the King of the Hill says, "propane is a cruel mistress".
"You do not laugh when you look at the mountains, or when you look at the sea." Lafcadio Hearn
"You do not laugh when you look at the mountains, or when you look at the sea." Lafcadio Hearn
|
Back to top |
|
|
moonspots Happy Curmudgeon
Joined: 03 Feb 2007 Posts: 2456 | TRs | Pics Location: North Dakota |
|
moonspots
Happy Curmudgeon
|
Mon Oct 31, 2016 7:59 pm
|
|
|
HitTheTrail wrote: | This is handy if you have a bunch of half used canisters and want to move the gas to make a full one. |
Won't work. Without a pumping system, the best you can do is fill each canister with 1/2 the volume of the two canisters in total. The "freezer/sun" bit might distribute the total gas in slightly disproportionate volumes, but I'd guess not by much.
"Out, OUT you demons of Stupidity"! - St Dogbert, patron Saint of Technology
"Out, OUT you demons of Stupidity"! - St Dogbert, patron Saint of Technology
|
Back to top |
|
|
HitTheTrail Member
Joined: 30 Oct 2007 Posts: 5455 | TRs | Pics Location: 509 |
RandyHiker wrote: | Have you had much success with actually doing that? |
When I got this thing I had 6 or 7 canisters laying around with anywhere from 20g to50g of gas in them. Now I have one that is full. In fact I tried to top it off with a full canister and got it over full by about 10g. Using the gas vent button I could get them down under 5g of gas and that was without using the cooling/warming trick. Under 5g I just vented them off with the button and punctured them for recycle.
My primary plan is to use a larger 500g canister to keep my 100g canister at around 50g each time I go out. That way I can shed a few ounces and will always have enough gas for cooking and coffee.
|
Back to top |
|
|
moonspots Happy Curmudgeon
Joined: 03 Feb 2007 Posts: 2456 | TRs | Pics Location: North Dakota |
|
moonspots
Happy Curmudgeon
|
Mon Oct 31, 2016 8:08 pm
|
|
|
HitTheTrail wrote: | RandyHiker wrote: | Have you had much success with actually doing that? |
When I got this thing I had 6 or 7 canisters laying around with anywhere from 20g to50g of gas in them. Now I have one that is full. |
Well, shut my mouth! Empirical evidence indicates that my understanding of physics is incorrect someway...unless you went out and *bought* a new, full canister.
"Out, OUT you demons of Stupidity"! - St Dogbert, patron Saint of Technology
"Out, OUT you demons of Stupidity"! - St Dogbert, patron Saint of Technology
|
Back to top |
|
|
HitTheTrail Member
Joined: 30 Oct 2007 Posts: 5455 | TRs | Pics Location: 509 |
The gas in the top canister is a liquid and is being pushed by gravity and the partial pressure of the gas vapor. The bottom canister has a vent button to release the vapor pressure in a one way valve so it is gravity and vapor on top vs vapor being vented on bottom. Gravity wins. BTW, I have a minor in physics.
|
Back to top |
|
|
moonspots Happy Curmudgeon
Joined: 03 Feb 2007 Posts: 2456 | TRs | Pics Location: North Dakota |
|
moonspots
Happy Curmudgeon
|
Tue Nov 01, 2016 7:27 am
|
|
|
HitTheTrail wrote: | The bottom canister has a vent button to release the vapor pressure in a one way valve so it is gravity and vapor on top vs vapor being vented on bottom. Gravity wins. |
The "weight" of the mass of liquid in the top canister (in addition to the vapor pressure) is sufficient to overcome the vapor pressure in the bottom canister enough to fill the bottom canister? And the bottom canister is vented to where? Outside?
I don't have a minor (or major) in physics, I'm just loosely comparing this to filling a tire from an air tank, where eventually (if left connected together with no intervention from me), both will come to the same pressure.
This seems implausible, so I'm trying to sort it out correctly. I'm assuming though that there has to be some threshold of imbalance in the mass of liquid in each canister at the start?
Would this work to completely fill a canister that is ~ 75% full from one that is say 25 or 30% full?
Can you explain how this works in more detail so I can follow it? Thanks.
"Out, OUT you demons of Stupidity"! - St Dogbert, patron Saint of Technology
"Out, OUT you demons of Stupidity"! - St Dogbert, patron Saint of Technology
|
Back to top |
|
|
forest gnome Forest nut...
Joined: 24 Apr 2003 Posts: 3520 | TRs | Pics Location: north cascades!! |
|
Back to top |
|
|
Backpacker Joe Blind Hiker
Joined: 16 Dec 2001 Posts: 23956 | TRs | Pics Location: Cle Elum |
While I appreciate the information, Ill just use and old one till it dies and bring a replacement.
Thanks HTT.
"If destruction be our lot we must ourselves be its author and finisher. As a nation of freemen we must live through all time or die by suicide."
— Abraham Lincoln
"If destruction be our lot we must ourselves be its author and finisher. As a nation of freemen we must live through all time or die by suicide."
— Abraham Lincoln
|
Back to top |
|
|
HitTheTrail Member
Joined: 30 Oct 2007 Posts: 5455 | TRs | Pics Location: 509 |
|
Back to top |
|
|
DigitalJanitor Dirt hippie
Joined: 20 May 2012 Posts: 792 | TRs | Pics
|
Too funny, husby has been 'sperimenting with this type of gas transfer widget + some super small/cheap knockoff Chinese stoves. He's inordinately pleased with himself and his ingenuity.
I'm sticking with the OH stove if I'm running the show.... I have an irrational paranoia about pressurized fuel systems especially after reading "Polar Dream".
|
Back to top |
|
|
Schenk Off Leash Man
Joined: 16 Apr 2012 Posts: 2372 | TRs | Pics Location: Traveling, with the bear, to the other side of the Mountain |
|
Schenk
Off Leash Man
|
Tue Nov 01, 2016 12:57 pm
|
|
|
Once the gas pressure equalizes between the 2 canisters then gravity will take over and the liquefied gas will drain into the lowest canister. I am sure the valve in question has this feature, a port to constantly equalize the pressure between the canisters.
Imagine 2 bottles of water put together the same way: Neck to neck with one bottle on top. There is no need for a pump to get the water to transfer from the top bottle to the lower bottle, especially if you introduce a way for the pressure to stay equalized between the two bottles (a straw in between the necks). Without that equalizing port/passage it would have to bubble and burp as the liquid transfers, but it will still do it.
This seems no more dangerous than refilling a butane lighter, and probably safer since you actually have a screw-on valve and you are not just holding a tight fit between the lighter and the refilling container.
Nature exists with a stark indifference to humans' situation.
Nature exists with a stark indifference to humans' situation.
|
Back to top |
|
|
|