How much fuel is left?

[Gamma1214]

I found this post on another board and thought it might be helpful to anyone here who uses backpacking stoves to cook or as back-up. If the location of the can is marked (outlined in sharpie?), the same balancing method should work with a canoe paddle instead of a hiking pole.

 

[Boatman53]

Very clever. I don’t use hiking poles but might be able to come up with something else to use.
Jim

 

[Gamma1214]

...might be able to come up with something else to use.

Jim, I thought, if the base of the can was traced on a paddle blade, a canoe paddle should work the same. Trick would be to get the can in the same spot every time (and, of course, take the same paddle on every trip).

 

[Boatman53]

I was thinking maybe a tent pole, maybe with a magnet to hold the can. More thoughts on this. A paddle might work, with the limitations you mentioned.
Jim

 

[Glenn MacGrady]

Clever trick, but it's not particularly useful to me to know exactly how much fuel is left in an isobutane canister. If I have one partially full canister, I just use whatever is in it, and if that's not enough for my trip, I then go to my full spares.

This video tests the burn times and various other measurements of nine different brands of 8 oz. isobutane canisters. I've set it to begin at the total burn time chart.

All nine 8 oz. canisters burn for about 2½ to 3 hours. Since I don't boil water for more than 12 minutes a day, I can easily compute how many isobutane canisters I need for a canoe trip. I usually use the 4 oz. canisters, so for them I figure about 75 minutes of burn time for each full canister. Therefore, one partial and one full canister should easily last me for a week solo, but I usually bring two full spares, which is not a big weight deal on canoe trip.

 

[PacketFiend]

Interesting trick, but it's basically just making a 100g-200g scale out of a hiking pole, and assumes both that all empty canisters weigh 100g, and that your poles aren't weighed down with dirt or water. I do take hiking poles with me, thanks to an ACL sprain I suffered a few years ago that can flare up at times. I might try this trick, although I'm not sure if I want to scratch up my $200 carbon hiking poles.

I find a better method is to float an empty and a full canister in water, and place marks in the same spots on canisters I take with me. MSR and JetBoil print those float marks on the canister at the factory, too.

Or, JetBoil makes a fuel canister scale: https://jetboil.johnsonoutdoors.com/parts-accessories/fuel-related/jetgauge
Costs $22USD and weighs 85 grams.

 

[Gamma1214]

I'm not sure if I want to scratch up my $200 carbon hiking poles

I wondered about that myself... Maybe he never heard of Sharpies(?)

 

[PacketFiend]

I wondered about that myself... Maybe he never heard of Sharpies(?)

The method he described was to find the balancing points using the blade of a knife. That way the blade is already exactly where it needs to be to put a mark on the pole. Then you place a sharpie mark where the scratches are. I assume also that sharpie marks will fade when put through a proper few portages or hikes.

I don't think this method would need to be that accurate, as both the weight of the canister and the fuel can vary 10% or 20%, depending on brand. And for me, I've mostly moved to liquid fuels, naptha or kerosene or alcohol, which don't have this problem. They've got 99 problems, but this ain't one.

 

[Odyssey]

Helpful links to fuel mixes.
https://www.trailgroove.com/blogs/entry/248-best-canister-fuel-for-backpacking-stoves/

Backpacking Stoves - Best Choices and Fuel Types - TrailGroove Blog

When it comes to backpacking stoves, there are several routes one can take and several different main categories of stoves exist, each with an array of pros ...

www.trailgroove.com

 

[jdeerfoot]

The last few years I increasingly camp in the shoulder seasons - early in the spring pre-bug and later in the fall after the leaves and people are gone. I have found that I can look at the condensation line on my fuel tanks to determine the amount of remaining fuel. I note the estimate in % on the plastic fuel container cap using a ballpoint pen. This works easily on 16 oz propane canisters and I assume it might work on iso canisters also but not sure since I frequently use liquid fuel backpacking stoves on solo trips.